TWI768697B - Friction roller molding die and friction roller - Google Patents

Abstract

Present invention discloses a friction roller molding die and a friction roller, wherein the friction roller has a hub and an elastic layer covering the outside of the hub, the molding die has a first molding board and a second molding board, a plurality of first cavities for molding the hub and plurality of second cavities for molding the elastic layer, upper portions of the first and second cavities are formed on a parting surface of the first molding board, lower portions of the first and second cavities are formed on a parting surface of the second molding board, an outer part of the lower portion of the each first cavity are formed by a plurality of first annular concave surfaces formed on a movable member of the second molding board, an outer part of the lower portion of the each second cavity are formed by a plurality of second annular concave surfaces, and the plurality of first annular concave surfaces are connected to the inside of the second annular concave surface.

Description

Friction Roller Forming Mould and Friction Roller

The invention relates to a friction roller forming die and a friction roller, in particular to a friction roller forming die and a friction roller used as a friction roller for false twisting.

The structure of the friction roller is usually composed of an elastic coating layer made of elastic plastic material (such as PU, NBR rubber, etc.) on the outer side of the hub.

Due to the complex shape of the wheel hub, most of the existing friction roller molding processes are processed by in-mold injection overmolding. The production process must first use injection molding molds or turning methods to manufacture the wheel hub components, and then the wheel hub components. It is placed in the mold for forming the elastic covering layer, and then the elastic covering layer is formed on the outer side of the wheel hub.

In the production process, the wheel hub and the elastic coating must be manufactured in two different processes, and the wheel hub needs to be manually or mechanically placed into the molding die, which prolongs the injection molding process time and leads to production. Efficiency is reduced.

Therefore, how to improve the problem of poor manufacturing efficiency of friction rollers through the improvement of structural design has become one of the important issues to be solved by this business.

The technical problem to be solved by the present invention is to provide a friction roller forming die and a friction roller in order to solve the problem of poor manufacturing efficiency of the existing friction roller.

In order to solve the above-mentioned technical problems, one of the technical solutions adopted by the present invention is to provide a friction roller forming mold, which includes a forming mold for manufacturing a friction roller, the friction roller has a hub and an elastic coating layer , the hub has a cylindrical outer side wall, and a rib extending outward from the outer side wall along the normal direction of the hub, and the elastic cladding layer covers the outer side wall of the hub and The outer side of the rib; the forming die can define a central axis, and define a first forming area and a second forming area located on both sides of the central axis, and the forming die includes: a first template and a second forming area; Two formwork, the first formwork and the second formwork are arranged opposite to each other, and the side face of the first formwork and the second formwork opposite to each other is defined as the parting surface, and the side facing the first formwork side is defined as the parting surface. The direction is defined as upward, and the direction toward the side of the second template is defined as downward. When the molding die is in the closed state, the parting surfaces of the first template and the second template are closed in a first template. The parting line; a plurality of first mold cavities, the shapes of the plurality of first mold cavities are complementary to the hub, so that the wheel hub can be formed, and the plurality of first mold cavities are arranged on all the forming molds. In the first molding area, the upper half of the first mold cavities are formed on the parting surface of the first template, and the lower half of the first mold cavities are formed on the second template. Parting surface; a plurality of second mold cavities, the plurality of second mold cavities can accommodate the hub and the elastic coating layer is formed on the outer side of the wheel hub, and the second mold cavities are arranged on the In the second forming area of the forming mold, the positions of the plurality of second cavities and the plurality of first cavities are symmetrical to the central axis, and the upper half of the plurality of second cavities The part is arranged on the parting surface of the first die plate, and the lower half of the second die cavity is arranged on the parting surface of the second die plate; the second die plate has a movable part and a plurality of first A fixing member and a plurality of second fixing members, the positions of the plurality of first fixing members correspond to the plurality of the first mold cavities, and the positions of the plurality of the second fixing members correspond to the plurality of the second fixing members A mold cavity, the movable part has a plurality of socket holes corresponding to a plurality of the first fixing parts and a plurality of the second fixing parts. When the movable part is in a closed position, a plurality of the first fixing parts The component and the plurality of the second fixing components are sleeved in the plurality of the socket holes, and when the movable component is displaced to a raised position, the movable component and the plurality of the first fixing components and the plurality of Each of the second fixed parts is separated from each other, and the movable part can rotate around the central axis, so that the movable part is located in the plurality of socket holes in the first molding area and in the plurality of socket holes in the first molding area. The positions of the plurality of socket holes in the second molding area are reversed with each other; a first concave portion is respectively provided on the top surface of each of the first fixing parts, and a first concave portion is respectively provided on the top surface of each of the second fixing parts A second lower concave portion, the movable member is provided with a first annular concave surface at the edge of each of the socket holes, and a first annular concave surface is connected to the outside of the first annular concave surface. A second annular concave surface, a plurality of the first lower concave portions can be connected with a plurality of the first annular concave surfaces to jointly define a lower half of the first cavity, and a plurality of the second lower concave portions Can be connected with a plurality of the second annular concave surfaces to jointly define a lower half of the second mold cavity; the shape of the plurality of first annular concave surfaces and a periphery of the rib of the hub The shape of the lower half of the portion is complementary, so that when the hub is formed in the first cavity, the peripheral portion of the rib can engage with the first annular concave surface; wherein, the After the forming mold forms the hub in the plurality of first mold cavities, the first mold plate and the second mold plate are separated from each other to form an open mold state, and the movable part is moved to the raised position. and then rotate about the central axis to move the plurality of hubs to positions aligned with the plurality of the second fixed parts, the movable parts are re-displaced to the closed position, and the first The mold plate and the second mold plate are closed to each other into a closed mold state, so that a plurality of the hubs are positioned in the second mold cavities, and plastic is wrapped around the wheel hubs through the second mold cavities and the outer side of the rib to form the elastic coating.

A preferred embodiment of the forming mold of the present invention further includes a first mold core, which is disposed on the first template, and the side of the first mold core facing the parting surface corresponds to a plurality of the first mold cores. A plurality of protruding portions are provided at the position of a mold cavity, a first upper concave portion is respectively provided on the bottom surface of each of the protruding portions, and the plurality of first upper concave portions form the upper half of the first mold cavity, and A plurality of second upper concave portions are provided on a side of the first mold core facing the parting surface corresponding to the positions of the plurality of the second mold cavities, and the plurality of the second upper concave portions form the second mold cavities the upper part of the .

In a preferred embodiment of the molding die of the present invention, when the molding die is in a closed state, a plurality of the protruding parts are accommodated in the second annular concave surface, and the outer edges of the protruding parts are and a plurality of the second annular concave surfaces are in close contact with each other, and when the molding die is in a closed state, a plurality of the first upper concave portions and a plurality of the first annular concave surfaces are connected to a second parting mold On the line, the height of the second parting line is lower than the first parting line, and the height of the second parting line from the first parting line is equal to or greater than the lower half of the second mold cavity The bottom surface of the part is spaced apart from the height of the first parting line.

In a preferred embodiment of the molding die of the present invention, the upper ends of the plurality of first fixing members form a first tapered portion, the upper ends of the plurality of second fixing members form a second tapered portion, and the upper ends of the plurality of the second fixing members form a second tapered portion. The inner side of the socket hole forms a tapered hole complementary to the first tapered portion and the second tapered portion.

A preferred embodiment of the molding die of the present invention, wherein the rotating part is connected to a rotating column, the rotating column is centered on the central axis, and can move back and forth along the central axis, and the central axis is The movable member can be driven to move back and forth between the closed position and the raised position, and the movable member can be driven to rotate around the central axis.

The embodiment of the present invention also provides a friction roller manufactured by using the friction roller forming die of the present invention.

The beneficial effect of the present invention lies in that the molding die can overcome the shape limitation of the friction roller, and can manufacture the friction roller by the double-material injection molding process, thereby achieving the purpose of improving production efficiency and reducing cost.

For a further understanding of the features and technical content of the present invention, please refer to the following detailed descriptions and drawings of the present invention. However, the drawings provided are only for reference and description, and are not intended to limit the present invention.

The following are specific embodiments to illustrate the embodiments of the "friction roller forming die and friction roller" disclosed in the present invention. Those skilled in the art can understand the advantages and effects of the present invention from the content disclosed in this specification. The present invention can be implemented or applied through other different specific embodiments, and various details in this specification can also be modified and changed based on different viewpoints and applications without departing from the concept of the present invention. In addition, the drawings of the present invention are merely schematic illustrations, and are not drawn according to the actual size, and are stated in advance. The following embodiments will further describe the related technical contents of the present invention in detail, but the disclosed contents are not intended to limit the protection scope of the present invention. In addition, the term "or", as used herein, should include any one or a combination of more of the associated listed items, as the case may be.

Referring to FIG. 1 to FIG. 3 , it is the structure of the friction roller 10 manufactured by the method and the mold of the present invention. The friction roller 10 has a hub 11 and an elastic coating layer 12 covering the outside of the hub 11 . The hub 11 is made of high-strength and high-hardness plastic materials (eg, polybutylene terephthalate PBT, polymethyl methacrylate PMMA, nylon Nylon, etc.), so that the hub 11 has high strength and It is not easy to deform, and the elastic coating layer 12 is made of rubber or silicone material with elasticity, high friction coefficient and wear resistance (such as: polyurethane rubber PU, nitrile rubber NBR, silicone rubber, etc.), so the present invention The friction roller 10 has good elasticity and friction, and can withstand the friction loss of high-speed rotation.

As shown in FIG. 2 , the friction roller 10 of the present invention can define a central axis C1 and a dividing line L1. Both the hub 11 and the elastic coating layer 12 of the friction roller 10 are centered on the central axis C1, and the dividing line L1 and the center The axes C1 are perpendicular to each other, and the hub 11 and the friction roller 10 can be divided into an upper half and a lower half by a dividing line L1.

As shown in FIG. 2 and FIG. 3 , the hub 11 is roughly cylindrical, and the center of the hub 11 has a shaft hole 13 . A rib 14 extends outward from the central position of the outer side of the cylinder of the hub 11 , and the outer side of the rib 14 forms a peripheral portion 16 having an arc-shaped cross-sectional shape. In this embodiment, both the hub 11 and the rib 14 are centered on the central axis C1, and the boundary line L1 passes through the center of the hub 11 and the rib 14, so the cross-sectional shape of the hub 11 is roughly symmetrical to the boundary lines L1 and 14. Center axis C1. The rib 14 is also provided with a plurality of through holes 15. After the friction roller 10 is formed, the elastic coating layer 12 covers the hub 11 and the outside of the rib 14, and part of the material of the elastic coating layer 12 flows into the rib. The elastic coating layer 12 and the rib 14 are firmly combined together.

The feature of the friction roller 10 of the present invention is that the hub 11 and the elastic coating layer 12 of the friction roller 10 are formed in the same molding die 20 through a double-material injection molding process, thus effectively shortening the process time and reducing labor consumption , and reduce the mold cost. The structure of the forming die 20 used in the friction roller 10 of the present invention and the manufacturing method thereof will be further described below. In particular, the friction roller 10 in this embodiment is the friction roller used by the false twisting machine, but other friction rollers, gravity rollers, etc. with similar structures can be manufactured by the molding die of the present invention.

As shown in FIG. 4 , the present invention is used to manufacture the forming die 20 of the friction roller 10 . The forming die 20 includes a first die plate 21 , a second die plate 22 , and a die set on the first die plate 21 and the second die plate 22 . The first mold core 30 and the second mold core 40. The forming mold 20 is divided by the central axis C2 and can be divided into a first forming area 23 and a second forming area 24 on the left and right sides. , and the forming mold 20 is provided with a plurality of second mold cavities 26 within the range of the second forming area 24 . The upper half of the plurality of first cavities 25 and the plurality of second cavities 26 are formed on one side of the parting surface of the first die plate 21 , and the upper half of the plurality of first cavities 25 and the plurality of second cavities 26 The lower half is formed on one side of the parting surface of the second die plate 22 .

The plurality of first mold cavities 25 and the plurality of second mold cavities 26 are cavities jointly defined by the first mold core 30 and the second mold core 40 . The shapes are complementary and can be used to form the hub 11 . The positions of the plurality of second mold cavities 26 and the plurality of first mold cavities 25 are symmetrical to each other with respect to the central axis C2, and the second mold cavities 26 substantially form cavities of a complementary shape to the friction roller 10, so that the hub 11 can be accommodated in the first mold cavity. In the two mold cavities 26 , the elastic coating layer 12 is formed on the outer side of the hub 11 and the rib to form the finished product of the friction roller 10 .

The first die plate 21 and the second die plate 22 can approach or move away from each other along a direction of a central axis C2, and the first die core 30 and the second die core 40 are respectively arranged on the first die plate 21 and the One side of the second template 22 that is close to each other, and can be driven by the first template 21 and the second template 22 to be closed or separated from each other. One side of the first mold core 30 and the second mold core 40 that are close to each other is defined as the parting surface. When the forming mold 20 is in the closed state, the first mold core 30 and the second mold core The parting surface of 40 is closed on a first parting line L2, so that the plurality of first mold cavities 25 and the second mold cavities 26 are in a closed state. When the forming mold 20 is in an open state, the first mold core 30 The mold core 40 and the second mold core 40 can be separated from each other by being driven by the first mold plate 21 and the second mold plate 22, so that the first mold cavity 25 and the second mold cavity 26 are in an open state. For convenience of description, the following description will define the direction toward the side of the second template 22 as the downward direction, and the direction toward the side of the first template 21 as the upper direction.

The detailed structure of the forming mold 20 will be described in further detail below. Please refer to FIGS. 4 to 6 at the same time. In this embodiment, the first mold core 30 is made of a metal fitted on the side of the first mold plate 21 close to the parting surface. The second mold core 40 is composed of a movable part 41 , a plurality of first fixing parts 42 and a plurality of second fixing parts 43 .

Among them, the movable part 41 is roughly in the shape of a plate, and the center of the movable part is connected with a rotating column 45. The rotating column 45 can rotate around the central axis C2 of the molding die 20, and can also move back and forth linearly along the direction of the central axis C2. Drive the movable part 41 to move back and forth between a closed position close to the second template 22 (as shown in FIG. 4 ) and a raised position away from the second template 22 (as shown in FIG. 8 ), and drive the movable part 41 The positions of the movable parts 41 in the range of the first molding area 23 and the second molding area 24 are reversed with each other by rotating with the central axis C2.

The positions of the plurality of first fixing members 42 correspond to the positions of the first mold cavity 25 respectively. In this embodiment, the first fixing members 42 are cylindrical, and the upper end of each first fixing member 42 forms a first cone The shape portion 421, the plurality of second fixing members 43 are arranged at the positions corresponding to the plurality of second mold cavities 26, the shape of the second fixing member 43 is cylindrical, and the upper end of the second fixing member 43 forms a second tapered portion 431 . The movable member 41 is provided with a plurality of socket holes 411 corresponding to the positions of the first fixed member 42 and the second fixed member 43 , and the socket holes 411 are in the shape of a cone complementary to the first tapered portion 421 and the second tapered portion 431 . Therefore, the plurality of socket holes 411 can be respectively fitted with the first tapered portions 421 and the second tapered portions 431 on the upper ends of the plurality of first fixing members 42 and the second fixing members 43 .

When the movable member 41 is in the closed position, the plurality of socket holes 411 are respectively fitted on the plurality of first tapered portions 421 and the plurality of second tapered portions 431, and the diameter and taper of the socket holes 411 are respectively the same as those of the first tapered portion 421 and the plurality of second tapered portions 431. The diameters and tapers of the first tapered portion 421 and the second tapered portion 431 are matched with each other, so that the plurality of socket holes 411 can be tightly fitted with the first tapered portion 421 and the second tapered portion 431, and as shown in FIG. 8 As shown, when the movable member 41 is displaced to the rising position, the socket hole 411 of the movable member 41 and the first tapered portion 421 and the second tapered portion 431 are separated from each other.

In particular, the positions of the plurality of first fixed parts 42 and the second fixed parts 43 of the molding die 20 of the present invention are symmetrical to the central axis C2, so when the movable part 41 rotates 180 degrees about the central axis C2, the positions of the first fixed parts 42 and the second fixed parts 43 in the After the positions of the plurality of socket holes 411 in the first molding area 23 and the plurality of socket holes 411 located in the second molding area 24 are reversed with each other, the plurality of socket holes 411 can be respectively connected to the plurality of first fixing components 42 and the plurality of socket holes 411. The first tapered portion 421 and the second tapered portion 431 of the second fixing member 43 fit together accurately.

In addition, a plurality of positioning taper holes 412 are provided on the movable member 41, and a plurality of tapered positioning posts 46 corresponding to the positioning taper holes 412 are provided on the second template 22. When the movable member 41 moves to the closed position, it can pass through The positioning tapered hole 412 and the tapered positioning post 46 are fitted with each other to locate the movable part 41 in the correct position.

As shown in FIGS. 4 and 5 , the structure of the first cavity 25 is shown. The first mold core 30 is provided with a plurality of protruding parts 31 in the range of the first molding area 23 , the position of each protruding part 31 corresponds to the position of the first mold cavity 25 , and each protruding part 31 is formed by the first The parting surface of the mold core 30 protrudes from the parting surface in the direction toward the second mold core 40 . A first upper concave portion 251 is formed on the bottom side of each protruding portion 31 . The shape of the first upper concave portion 251 is substantially complementary to the shape of the upper half of the hub 11 , thus forming the upper half of the first cavity 25 . part.

A first lower concave portion 252 is disposed on a top surface of the first fixing member 42 toward the first mold core 30 . The movable member 41 is provided with a first annular concave surface 253 and a second annular concave surface 263 located outside the first annular concave surface 253 on the edge of each socket hole 411 . The shape of the first annular concave surface 253 is substantially complementary to the shape of the lower half of the peripheral portion 16 of the rib 14 of the hub 11, and when the movable part 41 is in the closed position, the inner side of the first annular concave surface 253 The edge can be connected with the outer edge of the first lower recess 252 to form the lower half of the first cavity 25 together. And as shown in FIG. 5 , the outer edges of the protruding parts 31 on the first mold core 30 form a shape complementary to the second annular concave surface 263 . When the movable part 41 is in the closed position, the protruding parts 31 It is accommodated on the inner side of the second annular concave surface 263 , and the outer edge of the protruding portion 31 can closely fit with the second annular concave surface 263 .

As shown in FIG. 5 , when the molding die 20 is in a closed state, the first upper concave portion 251 , the first lower concave portion 252 , and the first annular concave surface 253 jointly define the first mold cavity 25 , and the first upper concave portion 251 and the outer edge of the first annular concave surface 253 are connected to each other on a second parting line L3. When the hub 11 is formed in the first cavity 25, the boundary line L1 of the hub 11 and the second parting line L3 are mutually connected. After overlapping, and the forming of the hub 11 is completed, the first mold cavity 25 can be parted along the second parting line L3, so that the wheel hub 11 can be removed from the first mold cavity 25 . It is worth noting that, since the plurality of first upper concave portions 251 are disposed on the bottom surface of the downwardly protruding protruding portion 31, and the upper edge of the first annular concave surface 253 is connected to the downwardly concave second annular concave surface 263 Therefore, the position of the second parting line L3 is lower than the height of the first parting line L2.

In particular, please refer to FIG. 5 and FIG. 6 at the same time, the upper edge outside the first annular concave surface 253 is connected to the lower edge inside the second annular concave surface 263, and the second annular concave surface 263 is used to form the second annular concave surface 263. The lower half of the outer edge of the cavity 26, and the second cavity 26 uses the first parting line L2 as the parting line (described in detail later), so the height of the upper edge of the first annular concave surface 253 will be equal to the first parting line L2. The height of the bottom surface of the lower half of the second mold cavity 26 . In other words, the height of the second parting line L3 of the first cavity 25 from the first parting line L2 is equal to the height of the bottom surface of the lower half of the second cavity 26 from the first parting line L2.

A first cylinder 422 is also disposed in the center of the first fixing member 42 , the upper end of the first cylinder 422 protrudes from the top surface of the first fixing member 42 , and the top end of the first cylinder 422 abuts against the top of the first upper concave portion 251 . the center of the face. The shape of the first cylinder 422 is complementary to the shape of the shaft hole 13 of the wheel hub 11 , and can be used to form the shaft hole 13 of the wheel hub 11 .

In addition, the first upper concave portion 251 and the first lower concave portion 252 are respectively provided with a plurality of upper bumps 2511 and lower bumps 2521 at positions corresponding to the plurality of through holes 15 on the rib portion 14 of the hub 11 . The upper bumps 2511 and the lower bumps 2521 are connected to each other, and the shapes of the upper bumps 2511 and the lower bumps 2521 are complementary to the shapes of the through holes 15 , so they can be used to form the rib 14 . A plurality of perforations 15 .

A plurality of first runners 27 are provided on the first die plate 21 to connect to the first mold cavity 25 , so as to inject plastic into the first mold cavity 25 to form the wheel hub 11 . In particular, in the preferred embodiment of the present invention, the first runner 27 can use a hot runner, so that the plastic accommodated in the first runner 27 can be kept in a molten temperature state, so when the first cavity 25 After the plastic inside is cooled and formed into the hub 11 , the plastic in the first runner 27 still maintains a molten state, and will not form a shoot center connected to the hub 11 . Therefore, after the forming of the wheel hub 11 is completed, there is no need to cut off the center of the shoot, which also reduces the amount of scraps.

As shown in FIG. 6 , the structure of the second cavity 26 is shown. In this embodiment, a plurality of second upper concave portions 261 are provided on the side of the first mold core 30 close to the parting surface corresponding to the positions of the plurality of second mold cavities 26 . the top half. The positions of the plurality of second fixing parts 43 correspond to the positions of the second upper concave parts 261 , and a second lower concave part 262 is provided on the second fixing parts 43 toward the top surface of the second upper concave part 261 . When the molding die 20 is in a closed state, the outer edge of the second lower concave portion 262 and the inner edge of the second annular concave surface 263 on the movable part 41 are adjacent to each other. As shown in FIG. 6 and FIG. 13 , the shape of the second lower concave portion 262 is complementary to the lower half of the hub 11 and the shape of the bottom side of the elastic coating layer 12 , and the shape of the second annular concave surface 263 is complementary to the shape of the elastic coating layer 12 . The shapes of the lower half of the outer edge of the coating 12 are complementary, so that the second lower recess 262 and the second annular recess 263 can jointly define the lower half forming the second cavity 26 when combined.

In addition, a second cylinder 432 is provided in the center of the second fixing part 43 , the upper end of the second cylinder 432 protrudes from the top surface of the second fixing part 43 , and the diameter of the second cylinder 432 is the same as the diameter of the shaft hole 13 in the center of the hub 11 . Cooperate with each other, so that when the hub 11 formed from the first cavity 25 is moved to the second cavity 26 for the second molding process, the shaft hole 13 of the hub 11 can be sleeved on the upper end of the second cylinder 432, so that the The hub 11 is positioned in the second cavity 26 .

As shown in FIGS. 4 , 6 , 12 and 13 , when the hub 11 is accommodated in the second cavity 26 , the upper and lower end surfaces of the hub 11 abut against the second upper concave portion 261 and the center of the second upper concave portion 261 respectively part, and the rib 14 of the hub 11 is also accommodated in the second cavity 26 . The first die plate 21 is provided with a plurality of second runners 28 in the range of the second molding area 24. The second runners 28 connect the plurality of second mold cavities 26 through the vertical gates 281 and the horizontal runners 282, and can The material for forming the elastic covering layer 12 is injected into the second cavity 26 . After the plastic is injected into the second mold cavity 26 , it can cover the outer sides of the hub 11 and the rib 14 to form the elastic coating layer 12 .

In addition, as shown in FIGS. 4 and 6 , the forming mold 20 is further provided with a plurality of ejection members 44 penetrating into the second cavity 26 and a plurality of penetrating horizontal flow channels 282 within the range of the second forming area 24 . The runner ejector pin 47, as shown in FIG. 14, when the molding die 20 is opened, the formed friction roller 10 and the runner connected to the friction roller 10 can be pushed through the ejector member 44 and the runner ejector pin 47. 17 is ejected, so that the friction roller 10 and the second cavity 26 are disengaged.

The manufacturing method and steps of the friction roller 10 of the present invention are further detailed below. The manufacturing method of the friction roller 10 of the present invention can be roughly divided into a first molding step, a mold changing step, a second molding step, and a demolding step.

As shown in FIG. 7 , in the first molding step, the molding mold 20 is in a closed state, and the plastic material for molding the hub 11 is injected into the first mold cavity 25 through the first runner 27 , and then the first mold cavity 25 is injected. The plastic in the cavity 25 cools and the plastic is formed into the hub 11 .

Next, as shown in FIGS. 8 to 11 , the operation mode of the molding die 20 during the die changing step is shown. As shown in FIGS. 8 and 9 , after the first molding step is completed, the first template 21 and the second template are 22 is separated to become the mold-opening state, and then the movable part 41 is driven to move to the ascending position by the rotating column 45 . As shown in FIG. 9 , after the hub 11 is formed, the peripheral portion 16 of the rib 14 will engage with the first annular concave surface 253 , so when the movable part 41 rises, the hub 11 can be driven to rise with the movable part 41 , And it is separated from the first lower concave portion 252 . Next, as shown in FIGS. 10 and 11 , after the movable part 41 is displaced to the rising position, the movable part 41 is then driven to rotate 180 degrees through the rotating column 45 , and the plurality of hubs 11 are moved to the second forming area 24 , and make Each socket hole 411 of the movable part 41 and the plurality of hubs 11 are aligned with the plurality of second fixed parts 43 , and then the movable part 41 is driven to descend to the closed position through the rotating column 45 , so that the socket holes 411 of the movable part 41 are Fitted with the second conical portion 431 at the upper end of the second fixing member 43 , the hubs 11 abut against the second concave portion 262 at the top end of the second fixing member 43 , and the upper end of the second cylinder 432 penetrates into the second concave portion 432 . in the shaft hole 13 in the center of the hub 11 .

As shown in FIG. 11 , after the mold changing step is completed, the hub 11 is driven by the movable part 41 to be displaced to the position of the second mold cavity 26 and positioned at the lower half of the second mold cavity 26 . It is worth noting that the height of the plurality of hubs 11 positioned in the second mold cavity 26 is higher than the height in the first mold cavity 25. Therefore, when the movable part 41 drives the wheel hubs 11 to descend against the second lower recess 262, The hub 11 will be lifted by the second lower recess 262, so that the peripheral portion 16 of the rib 14 of the hub 11 is separated from the first annular recess 253, and the dividing line L1 of the hub 11 is positioned at the first parting line. L2 equal height position.

Next, the second molding step is performed. As shown in FIGS. 12 and 13 , in the second molding step, the molding die 20 is in a closed state, so that the hub 11 is covered by the second cavity 26 . Then the second runner 28 injects the plastic for forming the elastic coating layer 12 into the second cavity 26 through the vertical gate 281 and the horizontal runner 282 , so that the plastic is formed into the elastic coating in the second cavity 26 . cladding 12 . In particular, when the molding die 20 performs the second molding step, it can also simultaneously inject plastic into the first die cavity 25 to form the hub 11 , so when the second molding process is completed, the first die cavity 25 is filled with plastic. At the same time, the hub 11 is formed and completed, so the production efficiency of the friction roller 10 can be effectively improved.

As shown in FIG. 14 , after the second molding step is completed, a demolding step is performed next. In the demolding step, the first and second mold plates 21 and 22 of the molding die 20 are separated to be in an open state, and can pass through a plurality of The ejector member 44 and the runner ejector pin 47 eject the formed friction roller 10 and the runner 17 connected between the plurality of rollers, so that the formed friction roller 10 and the second cavity 26 are separated, and the completion of Forming procedure of the friction roller 10 .

In particular, after the friction roller 10 of the present invention is formed, the runner 17 connected to the elastic coating layer 12 must be cut off, so that the elastic coating layer 12 will form a burr at the position where the runner 17 is cut off, and the plastic Infiltration into the parting line of the second die cavity 26 or the first annular concave surface 253 will also form burrs, so the burrs on the surface of the elastic coating layer 12 of the friction roller 10 can be cut off by turning or grinding, and further The shape and dimensions of the elastic coating 12 are trimmed to be within the tolerances required for the friction roller 10 .

In addition, as shown in FIG. 15, it is the second embodiment of the molding die of the present invention. In this embodiment, the first molding area 23 has two first runners 27a connected to the two first mold cavities 25, and the two The first runner 27a is a hot runner structure. And in the second molding area 24, there are two second runners 28a connected to the two second mold cavities 26, and the two second runners 28a also adopt the structure of hot runners. In this embodiment, since the second runners 28a are hot runners, each of the second runners 28a is directly connected to a second cavity 26, so the runner from the second runner 28a to the second cavity 26 is omitted. There are no cooling runners or cores on the elastic coating layer 12 after molding, which saves the consumption of injection molding materials and simplifies the subsequent processing procedures.

[Advantageous effects of the embodiment]

The beneficial effect of the present invention is that the molding die 20 can overcome the shape limitation of the friction roller 10, and can manufacture the friction roller 10 by a two-material injection molding process, thereby achieving the purpose of improving production efficiency and reducing cost.

The contents disclosed above are only preferred feasible embodiments of the present invention, and are not intended to limit the scope of the present invention. Therefore, any equivalent technical changes made by using the contents of the description and drawings of the present invention are included in the application of the present invention. within the scope of the patent.

10: Friction roller 11: Wheels 12: Elastic cover 13: Shaft hole 14: Ribs 15: Perforation 16: Peripheral part 17: runner 20: Forming mold 21: The first template 22: Second Template 23: The first forming area 24: The second forming area 25: The first cavity 251: First upper recess 2511: Upper bump 252: The first lower recess 2521: Lower bump 253: The first annular concave surface 26: The second cavity 261: Second upper recess 262: Second lower recess 263: Second annular concave surface 27, 27a: The first runner 28, 28a: Second runner 281: Vertical gate 282: Horizontal runner 30: The first mold 31: Projection 40: The second mold 41: Moving Parts 411: socket hole 412: Positioning taper hole 42: The first fixed part 421: First taper 422: The first cylinder 43: Second fixed part 431: Second taper 432: Second Cylinder 44: Ejection member 45: Spinning column 46: Conical positioning post 47: Sprue ejector pin C1, C2: central axis L1: dividing line L2: The first parting line L3: Second parting line

FIG. 1 is a schematic perspective view of the friction roller of the present invention.

Figure 2 is a schematic cross-sectional view of the friction roller of the present invention.

3 is a schematic cross-sectional view of the hub of the friction roller of the present invention.

FIG. 4 is a schematic cross-sectional view of the combination of the friction roller forming die of the present invention.

FIG. 5 is a partially enlarged combined cross-sectional schematic diagram of the first cavity of the friction roller forming die of the present invention.

FIG. 6 is a partially enlarged combined cross-sectional schematic diagram of the second cavity of the friction roller forming die of the present invention.

7 is a schematic cross-sectional view of the friction roller forming die of the present invention in a state in which the first forming step is performed.

FIG. 8 is a schematic cross-sectional view of the friction roller forming die of the present invention in the state in which the die changing step is performed.

FIG. 9 is a schematic partial enlarged cross-sectional view taken from part IX of FIG. 8 .

10 is a schematic cross-sectional view of the friction roller forming die of the present invention in a state where the die changing step is completed.

FIG. 11 is a schematic partial enlarged cross-sectional view taken from part XI of FIG. 10 .

12 is a schematic cross-sectional view of the friction roller forming die of the present invention in a state in which the second forming step is performed.

FIG. 13 is a partially enlarged schematic cross-sectional view taken from the part XIII of FIG. 12 .

FIG. 14 is a schematic cross-sectional view of the friction roller forming die of the present invention in the state in which the demolding step is performed.

15 is a schematic cross-sectional view of a combination of a modified embodiment of the hot runner structure used for the first and second runners of the friction roller forming die of the present invention.

20: Forming mold

21: The first template

22: Second Template

23: The first forming area

24: The second forming area

25: The first cavity

26: The second cavity

27: First runner

28: Second runner

30: The first mold

40: The second mold

41: Moving Parts

411: socket hole

412: Positioning taper hole

42: The first fixed part

43: Second fixed part

44: Ejection member

45: Spinning column

46: Conical positioning post

47: Sprue ejector pin

C2: central axis

L2: The first parting line

Claims (10)

A friction roller forming die is used to manufacture a friction roller, the friction roller has a hub and an elastic cladding layer, the hub has a cylindrical outer side wall, and a groove extending from the outer side wall along the hub is provided. a rib extending outward in a normal direction, the elastic cladding layer covers the outer sidewall of the hub and the outer side of the rib; the forming die can define a central axis, and define a The first forming area and the second forming area on both sides of the central axis, the forming mold includes: The first formwork and the second formwork, the first formwork and the second formwork are arranged opposite to each other, and one side of the first formwork and the second formwork opposite to each other is defined as a parting surface, facing the first formwork. The direction of one side of the template is defined as upward, and the direction toward the side of the second template is defined as downward. When the forming mold is in the closed state, the parting surfaces of the first template and the second template are closed on a first parting line; A plurality of first mold cavities, the shapes of the plurality of first mold cavities are complementary to the hub, so that the wheel hub can be formed, and the plurality of first mold cavities are arranged in the first molding of the molding die The upper half of the first mold cavity is formed on the parting surface of the first mold plate, and the lower half of the first mold cavity is formed on the mold parting surface of the second mold plate. ; A plurality of second mold cavities, a plurality of the second mold cavities can accommodate the hub and the elastic coating is formed on the outer side of the wheel hub, and the second mold cavities are arranged on the outer side of the molding die In the second molding area, the positions of the plurality of second mold cavities and the plurality of first mold cavities are symmetrical to the central axis, and the upper half of the plurality of second mold cavities are arranged in the On the parting surface of the first template, the lower half of the second mold cavity is arranged on the parting surface of the second template; A plurality of first runners, a plurality of the first runners are respectively connected to a plurality of the first mold cavities, and a plurality of second runners, a plurality of the second runners are respectively connected to the plurality of the The second mold cavity, the plurality of first runners and the plurality of second runners are hot runners; The second template has a movable part, a plurality of first fixing parts and a plurality of second fixing parts, the positions of the plurality of the first fixing parts correspond to the plurality of the first mold cavities, and the plurality of the first fixing parts are located. The positions of the two fixing parts correspond to a plurality of the second mold cavities, and the movable part has a plurality of socket holes corresponding to the plurality of the first fixing parts and the plurality of the second fixing parts. When in a closed position, a plurality of the first fixing parts and a plurality of the second fixing parts are sleeved in the plurality of the socket holes, and when the movable part is displaced to a rising position, the The movable part and the plurality of the first fixing parts and the plurality of the second fixing parts are separated from each other, and the movable part can rotate around the central axis, so that the movable part is located in the first molding The positions of the plurality of socket holes in the zone and the plurality of socket holes in the second forming zone are reversed with each other; The top surface of each of the first fixing parts is respectively provided with a first lower concave part, the top surface of each of the second fixing parts is respectively provided with a second lower recessed part, and the movable part is located in each of the socket holes. A first annular concave surface and a second annular concave surface connected to the outside of the first annular concave surface are respectively set on the edges of the Commonly define and form the lower half of the first mold cavity, and a plurality of the second lower concave portions can be connected with a plurality of the second annular concave surfaces to jointly define the lower half of the second mold cavity; The shape of the plurality of first annular concave surfaces is complementary to the shape of the lower half of a peripheral portion of the rib portion of the hub such that when the hub is formed in the first cavity, the the peripheral portion of the rib can engage with the first annular concave surface; Wherein, after the forming mold forms the hub in the plurality of first mold cavities, the first mold plate and the second mold plate are separated from each other to form an open mold state. After the raised position is rotated about the central axis, and the plurality of hubs are moved to positions aligned with the plurality of the second fixed members, the movable member is re-displaced to the closed position, and all The first mold plate and the second mold plate are closed to each other into a closed mold state, so that a plurality of the hubs are positioned in a plurality of the second mold cavities, and the plastic is coated on the plastic through the second mold cavities. The outer side surfaces of the hub and the rib form the elastic cladding layer. The friction roller forming mold according to claim 1, further comprising a first mold core disposed on the first template, the side of the first mold core facing the parting surface corresponding to a plurality of The position of the first mold cavity is provided with a plurality of protruding parts, the bottom surface of each protruding part is respectively provided with a first upper concave part, and the plurality of first upper concave parts form the upper half of the first mold cavity , and the side of the first mold core facing the parting surface is provided with a plurality of second upper concave portions corresponding to the positions of the plurality of the second mold cavities, and the plurality of the second upper concave portions form the second upper concave portions. The upper part of the cavity. The friction roller forming die according to claim 2, wherein when the forming die is in a closed state, a plurality of the protruding parts are accommodated in the second annular concave surface, and a plurality of the protruding parts are The outer edge and the plurality of second annular concave surfaces are in close contact with each other. The friction roller forming die according to claim 3, wherein when the forming die is in a closed state, a plurality of the first upper concave parts and a plurality of the first annular concave surfaces are connected to a second parting mold On the line, the height of the second parting line is lower than that of the first parting line. The friction roller forming mold according to claim 4, wherein the height of the second parting line from the first parting line is equal to or greater than the distance between the bottom surface of the lower half of the second cavity and the first parting line. The height of a parting line. The friction roller forming die according to claim 1, wherein the upper ends of the plurality of first fixing members form a first tapered portion, the upper ends of the plurality of second fixing members form a second tapered portion, and the plurality of upper ends of the second fixing members form a second tapered portion. A tapered hole complementary to the first tapered portion and the second tapered portion is formed on the inner side of the socket hole. The friction roller forming die according to claim 1, wherein the rotating part is connected to a rotating column, the rotating column is centered on the central axis and can be reciprocally displaced along the central axis, and the rotating column is centered on the central axis. The axis is rotated as the center, and the movable part can be driven to move back and forth between the closed position and the raised position, and the movable part can be driven to rotate around the center axis. The friction roller forming die according to claim 1, wherein a plurality of conical positioning posts are arranged on the second template, and a plurality of the positioning cones are arranged on the movable part corresponding to the positions of the plurality of the conical positioning posts When the rotating module is in the closed position, a plurality of the positioning tapered holes and a plurality of the tapered positioning posts are sleeved. A friction roller, which is manufactured by using the friction roller forming die according to any one of claims 1 to 8. The friction roller according to claim 9, wherein the friction roller is a friction roller for false twisting or a gravity roller.

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