JP5292168B2 - Cylindrical part manufacturing method and cylindrical part manufacturing mold - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a cylindrical part by which the cylindrical part in which no weld line is generated and there is no gate cut mark in an inner peripheral face can be manufactured at low cost. <P>SOLUTION: In the method for manufacturing the cylindrical part for manufacturing the cylindrical part 50 using a mold 1 having a molten metal channel 10 for feeding molten metal to a part forming section 31 from a runner 11 via a gate 22, the molten metal is fed to a molten metal running section 17 arranged in a circular shape along the outside of the part forming section 31 to fill the same with the molten metal and the part forming section 31 is filled with the molten metal by flowing the molten metal filling the molten metal running section 17 from the outer periphery side of the part forming section 31. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a cylindrical part manufacturing method and a cylindrical part manufacturing mold for manufacturing a cylindrical part using a mold.

  Since the manufacturing cost of a part is reflected in the cost of a product using the part, various studies for suppressing the manufacturing cost have been conducted. For example, when manufacturing a part using a mold, after the molten metal is filled into the part molding part through a runner from a closed mold sprue, the mold is cooled, and then the mold is opened to take out the molded product. For example, parts can be mass-produced at low cost with a single shot.

  For example, in the method of manufacturing a cylindrical part shown in FIG. 20, the molten metal supplied from the gate 101 to the part molding part 102 is divided into two parts and flows through the cylindrical part molding part 102, on the opposite side of the gate 101 about 180 degrees. After merging, it further flows from the component forming portion 102 to the hot water pool 104 via the communication portion 103. Thereby, in the part which a molten metal merges and contacts, since a pressure becomes imbalance and a contact area becomes large, the intensity | strength of a molten metal merged part becomes strong for cylindrical components (for example, refer patent document 1).

  Further, for example, in the cylindrical part manufacturing method shown in FIG. 21, the molten metal is supplied from the spool 111 to the thin disk-like runner 112 and is supplied uniformly from the gate 113 to the inside of the part forming part 114. No weld line occurs in the part molded at 114. The molded product taken out from the mold is cut at the gate portion, and the cylindrical part is separated (see, for example, Patent Document 2).

JP 2002-301742 A JP 2000-263600 A

  However, in the method of manufacturing a cylindrical part shown in FIG. 20, a weld line is generated at the joining part of the molten metal that has flowed in two parts in the part forming part 102. For example, when the cylindrical part is an annular seal member and a weld line is generated on the seal surface, a highly permeable fluid may leak to the outside through the weld line. In order to solve such a problem, it is conceivable to remove the weld line by cutting, but there is a problem that the number of processing steps increases and the cost increases.

  On the other hand, in the manufacturing method of the cylindrical part shown in FIG. 21, a gate cut mark is generated on the inner peripheral surface of the cylindrical part. For example, when the cylindrical part is an annular seal member whose inner peripheral surface constitutes a flow path when mounted on the component connection portion, if there is a gate cut mark on the inner peripheral surface, the fluid flowing in the flow path is disturbed. There is a problem of causing flow and stagnation.

  The present invention has been made to solve the above-described problems, and a cylindrical part manufacturing method that can inexpensively manufacture a cylindrical part that does not have a weld line and has no gate cut trace on the inner peripheral surface, and An object is to provide a mold for manufacturing a cylindrical part.

The cylindrical part manufacturing method and cylindrical part manufacturing die according to the present invention have the following configurations.
(1) In a cylindrical part manufacturing method for manufacturing a cylindrical part using a mold having a molten metal flow path for supplying a molten metal from a runner to a part molding part via a gate, along the outside of the part molding part. Supplying and filling the molten metal in a ring-shaped hot water supply section, filling the molten metal filled in the hot water flow section from the outer peripheral side of the component molding section, and filling the input runner section of the runner After being supplied, the molten metal is diverted through the first runner portion at the first connection runner portion provided symmetrically by 180 degrees with respect to the input runner portion, and the second runner portion inside the first runner portion. Through the second connection runner portion provided symmetrically with respect to the first connection runner portion and at intervals of 90 degrees, and supplied to the outer periphery of the hot water supply portion at equal intervals in the circumferential direction. In addition, the parts Supplying uniformly a molten metal in a circumferential direction to part.

( 2 ) In the invention described in (1) , a flow rate of the molten metal flowing from the hot water supply portion to the communication portion is provided in a ring shape between the inner side of the hot water supply portion and the outer side of the component molding portion. The molten metal is supplied from the communication part from the outside of the part forming part.

( 3 ) In the invention described in (1) , a communicating portion is provided radially between the inner side of the hot water portion and the outer side of the component molding portion, and the hot water portion is circumferentially provided on the component molding portion. Connected at equal intervals, the flow rate of the molten metal flowing from the hot water flowing portion to the communicating portion is reduced, and the molten metal is supplied from the communicating portion from the outside of the component forming portion.

( 4 ) Used for manufacturing a cylindrical part having a cylindrical shape, a part molding part corresponding to the cylindrical part, a runner for flowing a molten metal to the part molding part, and the molten metal from the runner to the part molding part. In the cylindrical part manufacturing mold having a gate to be supplied, the runner includes an annular hot water part provided concentrically with the part molding part on the outside of the part molding part, and An input runner portion for inputting the molten metal; a communication portion for communicating the inner side with the outer side of the component forming portion; and a runner portion for filling the molten metal into the molten metal portion. And a first runner portion that flows through the molten metal supplied from the input runner portion; a first connection runner portion that divides the molten metal flowing through the first runner portion and is provided 180 degrees symmetrically with respect to the input runner portion; The first A second runner part that is provided inside the runner part and flows through the molten metal supplied from the first connection runner part; and a molten metal that flows through the second runner part is divided into a symmetrical position with respect to the first connection runner part. And a second connection runner portion provided at intervals of 90 degrees, and connected in the circumferential direction to the hot water circulating portion .

( 5 ) In the invention described in (4), the communication portion includes an inner opening that has an outer opening width that opens in the hot water circulating portion that is smaller than a flow path width of the hot water circulating portion and that opens in the component molding portion. The width is smaller than the flow path width on the outer periphery of the component molding portion.

( 6 ) In the invention described in ( 5 ), the communication portion is provided annularly or radially between the hot water circulating portion and the component molding portion.

  In the above cylindrical part manufacturing method and cylindrical part manufacturing mold, the molten metal is supplied and filled in the annular portion of the hot water provided annularly along the outside of the molded part, and the molten metal is molded from the molten metal part. Since it flows evenly to the outside of the part and fills, the molten metal flows so as to constrict the circle from the outside to the inside of the part forming part. For this reason, in the component molding part, there is no place where the tip ends of the molten metal flowing in two directions meet, and no weld line is generated in the cylindrical part molded in the component molding part. In addition, since the gate is provided outside the component forming portion and the molten metal is supplied, the gate cut mark does not remain on the inner peripheral surface of the cylindrical component. In addition, the mold flow path structure that supplies molten metal evenly from the outside of the molded part prevents the occurrence of weld lines and gate cut traces, so that cutting to remove weld lines and gate cut traces is possible. There is no need to do this, and cylindrical parts can be manufactured at low cost.

  Then, the cylindrical part is separated from the molded product by cutting the molded product taken out from the mold at a position between the gate and the part molding part, so that the gate cut mark is formed on the outer peripheral surface of the cylindrical part. It remains, and it can be easily determined whether or not it is manufactured using the above manufacturing method and mold.

  When the cylindrical part manufactured in this way is an annular seal member, no weld line is generated on the seal surface, so even when a highly permeable fluid is used, the fluid leaks to the outside through the weld line. There is no. Further, since the annular seal member manufactured as described above has no irregularities due to gate cut marks on the inner peripheral surface forming the flow path surface, when the fluid flows along the inner peripheral surface of the annular seal member, the inner peripheral surface There is no turbulent flow or stagnation due to the gate cut marks on the surface, and the fluid replacement and cleanliness are improved.

It is a schematic block diagram of the metal mold | die which concerns on 1st Embodiment of this invention. It is an external appearance perspective view of an annular seal member. It is a figure which shows an example of the connection part seal structure sealed using an annular seal member. It is a conceptual diagram of a molten metal flow path. It is AA sectional drawing of FIG. It is BB sectional drawing of FIG. It is CC sectional drawing of FIG. It is a figure for demonstrating the flow of molten resin, Comprising: A mode that molten resin flows from a 1st runner part to a 3rd runner part via a 2nd runner part is shown. It is a figure for demonstrating the flow of molten resin, Comprising: A mode that molten resin flows from a 3rd runner part to a hot-water part is shown. It is a figure for demonstrating the flow of molten resin, Comprising: A mode that molten resin flows from a hot-water part to a communicating part is shown. It is a figure for demonstrating the flow of molten resin, Comprising: A mode that molten resin flows from a communicating part to a component shaping | molding part is shown. It is a figure for demonstrating the flow of molten resin, Comprising: A mode that molten resin flows into the main body shaping | molding part of a component shaping | molding part is shown. It is a figure for demonstrating the flow of molten resin, Comprising: The mode that filling with the molten resin to a component formation part was completed is shown. It is a conceptual diagram of the molten metal flow path provided in the metal mold | die which concerns on 2nd Embodiment of this invention. It is DD sectional drawing of FIG. It is EE sectional drawing of FIG. It is FF sectional drawing of FIG. It is a figure for demonstrating the flow of molten resin, Comprising: A mode that molten resin flows from a hot-water part to a communicating part is shown. It is a figure for demonstrating the flow of molten resin, Comprising: A mode that molten resin flows from a communicating part to a component shaping | molding part is shown. It is a figure which shows the 1st prior art example of the resin component manufacturing method. It is a figure which shows the 2nd prior art example of the resin component manufacturing method.

  Hereinafter, an embodiment of a method for manufacturing a cylindrical part and a mold for manufacturing a cylindrical part according to the present invention will be described with reference to the drawings.

(First embodiment)
<Schematic configuration of mold>
FIG. 1 is a schematic configuration diagram of a mold 1.
A mold 1 shown in FIG. 1 is used for manufacturing a resin annular seal member (an example of a cylindrical part) 50 shown in FIG. When the mold 1 is closed by moving the movable mold 3 toward the fixed mold 2 so as to bring the core 5 into contact with the cavity 4, the molten metal flow path 10 to be described later is formed by a groove formed on the contact surface between the core 5 and the cavity 4. (See FIGS. 4 to 7). In the mold 1, an injection molding machine (not shown) is connected to the sprue 6 of the fixed mold 2, and molten resin is supplied from the sprue 6 to a molten metal flow path 10 (see FIGS. 4 to 7) described later. The mold 1 is temperature-adjusted using a heater (not shown) to prevent solidification of the molten resin during injection molding, and ensures the fluidity of the molten resin until the molten resin is completely filled in the molten metal flow path 10. After the molding is completed, the heater is stopped to cool and completely solidify. After the movable mold 3 is moved away from the fixed mold 2 and the mold 1 is opened, the molded product 7 is pushed out from the movable mold 3 by an ejector pin (not shown) built in the mold 1 and taken out. In the molded product 7, since the annular seal member 50 is formed in the center, the annular seal member 50 is separated by cutting a gate portion provided on the outer periphery of the annular seal member 50 by punching or the like.

<Annular seal member and seal structure using the same>
FIG. 2 is an external perspective view of the annular seal member 50. FIG. 3 is a view showing an example of a seal structure for sealing using the annular seal member 50.
An annular seal member 50 shown in FIG. 2 is attached to a connection portion between the first connection portion 62 of the first component 61 and the second connection portion 72 of the second component 71, for example, as shown in FIG. . In the annular seal member 50, the cylindrical main body 51 has a first annular seal groove 63 formed on the end face of the first connection part 62 and a second annular seal groove 73 formed on the end face of the second connection part 72. Installed. An annular groove 54 is formed on one end surface of the main body 51 to fit into a first annular protrusion 64 provided concentrically with the first annular seal groove 63, and a second annular ring is formed on the other end surface of the main body 51. An annular groove 55 that fits into a second annular protrusion 74 provided concentrically with the seal groove 73 is formed. The annular seal member 50 is provided with press-fitting allowances 56 and 57 on the inner side surface and the outer side surface of the annular grooves 54 and 55, respectively, and press-fits the first and second annular projections 64 and 74 to perform an interference fit. The second connection parts 62 and 72 are sealed in the radial direction.

  The main body 51 protrudes from the central portion of the outer peripheral surface so that the overhang 52 protrudes in the outer diameter direction, and a plurality of gripping portions 53 are provided on the outer edge of the overhang 52. The overhang portion 52 is provided in a thin disc shape so as not to obstruct the connection of the first and second connection portions 62 and 72. The grip portion 53 is provided so that the inner peripheral surface thereof is parallel to the outer peripheral surface of the main body portion 51. When the annular seal member 50 is mounted in the first and second annular seal grooves 63 and 73, The annular grooves 54 and 55 are positioned with respect to the second annular protrusions 64 and 74. The annular seal member 50 is provided with a hooking portion 58 provided at one end of the gripping portion 53 on the outer periphery of the end surface of the first or second connecting portion 62, 72 when the first and second connecting portions 62, 72 are connected. It is hooked on the locking projections 65 and 75 and is prevented from falling off.

<Configuration of molten metal flow path>
FIG. 4 is a conceptual diagram of the molten metal flow path 10. FIG. 5 is a cross-sectional view taken along the line AA in FIG. FIG. 6 is a BB cross-sectional view of FIG. FIG. 7 is a CC cross-sectional view of FIG.
In the molten metal flow path 10, a runner 11 and a gate 22 are provided concentrically with a part molding portion 31 provided corresponding to the annular seal member 50, and the melt supplied to the runner 11 from the sprue 6 (see FIG. 1). The resin is uniformly supplied from the gate 22 to the outside of the component molding portion 31, and the molten resin is flowed from the outside to the inside of the component molding portion 31 to fill the component molding portion 31.

  As shown in FIGS. 4 to 7, the component molding portion 31 includes a main body molding portion 32 for molding the main body portion 51 of the annular seal member 50 and a tension for molding the protruding portion 52 of the annular seal member 50. A take-out molding part 33 and a grip molding part 34 for molding the grip part 53 of the annular seal member 50 are provided. The grip forming portions 34 are provided at equal intervals in the circumferential direction outside the overhang forming portion 33. As shown in FIG. 4 and FIG. 7, the hot water flow passage portion 35 is provided so as to connect the grip forming portions 34 provided at equal intervals on the circumference, and communicates with the overhang forming portion 33. . As shown in FIG. 7, in the hot water flow passage portion 35, the radial width dimension of the annular seal member 50 is the same as that of the gripping molding portion 34, and the axial width dimension of the annular seal member 50 is the gate 22 and the overhang molding. The molten resin that has flowed from the gate 22 to the part molding part 31 flows around the gripping molding part 34 and the hot water flow path part 35 before filling and flows into the bulging molding part 33. To be.

  As shown in FIG. 4, the runner 11 is provided with a communication portion 18 and a hot water supply portion 17 concentrically with the part forming portion 31 in an annular shape, and the melt supplied from the sprue 6 (see FIG. 1) to the input runner portion 12. The resin is diverted to the first connection runner portions 14a and 14b via the first runner portion 13, and further branched to the second connection runner portions 16a, 16b, 16c and 16d via the second runner portions 15a and 15b. The hot water is supplied to the hot water supply section 17.

In order to allow the molten resin to flow uniformly from the donut-shaped hot water portion 17 and the communication portion 18 toward the center of the part molding portion 31, the pressure of the molten resin filled in the hot water portion 17 is made uniform in the circumferential direction. Then, it is necessary to supply molten resin from the hot water supply part 17 to the component molding part 31 through the communication part 18.
Therefore, the second connection runner portions 16 a to 16 d are arranged at equal intervals in the circumferential direction outside the hot water circulating portion 17 and are connected to the hot water circulating portion 17. The second connection runners 16 a to 16 d are provided at positions corresponding to the grip molding part 34 having a larger volume than the hot water flow path part 35 in the part molding part 31, and are connected to the grip molding part 34 from the hot water flow path part 35. The molten resin is easily filled, so that the amount of the molten resin is less likely to vary in the circumferential direction.

  Further, in order to allow the molten resin supplied to the input runner portion 12 to be evenly divided and input from the outside of the part forming portion 31, the runner 11 is connected to the outside of the hot water circulating portion 17. The number of 16d is an even number. In other words, the runner 11 includes the first connection runner portions 14a and 14b branched from the input runner portion 12 via the first runner portion 13 in order to allow the molten resin to flow evenly at symmetrical positions with the component molding portion 31 in between. They are provided at symmetrical positions with the molding part 31 in between. Further, in order to evenly supply the molten resin to the hot water circulating portion 17 in the circumferential direction, the second runner portion 16a and 16b are arranged at symmetrical positions with the first connection runner portion 14a interposed therebetween. 15a is provided, and the second runner portion 15b is provided so that the second connection runner portions 16c and 16d are arranged at symmetrical positions with the first connection runner portion 14b interposed therebetween.

  Further, as shown in FIGS. 5 to 7, the input runner portion 12, the first runner portion 13, the first connection runner portions 14a and 14b, the second runner portions 15a and 15b, the second connection runner portions 16a to 16d, and hot water. The cross section of the flow path of the surrounding part 17 is made into the same circular shape, so that the molten resin flows from the input runner part 12 to the hot water surrounding part 17 without pressure loss (resistance). As shown in FIG. 7, the communication portion 18 has an opening that opens to the hot water circulating portion 17 smaller than the flow path diameter of the hot water circulating portion 17, and before the molten resin is filled in the hot water circulating portion 17, It is difficult to flow in.

  In such a runner 11, in order to allow the molten resin filled in the hot water circulating portion 17 to flow evenly toward the center of the part molding portion 31, the opening width at which the communication portion 18 opens in the hot water circulating portion 17 is set. The flow rate of the molten resin flowing from the hot water supply portion 17 toward the component molding portion 31 is reduced. Further, the communication portion 18 has an opening width of the gate 22 that is smaller than a flow passage width of the outer peripheral portion of the component forming portion 31 (the grip forming portion 34 and the hot water flow passage portion 35), and Since the opening width is smaller than the flow path width of the outer peripheral part of the part molding part 31, before the molten resin flows to the overhang molding part 33, the grip molding part 34 and the hot water flow path part 35 are uniformly filled in the circumferential direction. I try to do it.

  Here, in the communication part 18, the throttle channel part 19, the hot water channel part 20, and the throttle channel part 21 are continuously provided concentrically from the outside toward the inside. The hot water channel portion 20 has a larger channel width than the throttle channel portions 19 and 21, and once the molten resin that has flowed through the throttle channel portion 19 is stored in the hot water channel portion 20, the throttle channel portion 21. It is made to flow to the component molding part 31 via. Thereby, the communication part 18 allows the molten resin flowing from the outside to the inside to flow so as to constrict the circle, and allows the molten resin to be uniformly input to the entire outer periphery of the component molding part 31.

<Manufacturing method of cylindrical part>
Next, an injection molding method for the annular seal member 50 will be described. 8 to 13 are diagrams for explaining the flow of the molten resin. The dot portion in the figure indicates the region where the molten resin has flowed.
The mold 1 shown in FIG. 1 is closed, and a molten resin obtained by melting a fluororesin is supplied to the input runner 12 by supplying pressure to the sprue 6 from an injection device (not shown). As shown in FIG. 8, the molten resin flows equally divided into the first connection runner portions 14a and 14b separated from the input runner portion 12 by the same distance, and flows to the second runner portions 15a and 15b. Then, the molten resin flows evenly to the second connection runner portions 16a and 16b separated by the same distance from the second runner portion 15a, and flows into the hot water circulating portion 17 with a phase difference of 90 degrees. Further, the molten resin flows equally to the second connection runner portions 16c and 16d separated by the same distance from the second runner portion 15b, and flows into the hot water circulating portion 17 with a phase difference of 90 degrees. Since the opening width of the communication part 18 is smaller than the flow path diameter of the hot water circulating part 17 and the viscosity of the molten resin is high, as shown in FIG. 9, from each of the second connection runner parts 16a to 16d to the hot water circulating part 17 The supplied molten resin does not flow into the communication part 18 but flows equally in two directions along the hot water circulating part 17. Then, the molten resin joins the tip portions and fills the hot water supply portion 17.

  Thereafter, the molten resin filled in the hot water circulating portion 17 flows out so as to be squeezed out from the hot water circulating portion 17 to the communication portion 18 by the pressure of the subsequent molten resin, and the communication portion 18 is circled from the outside to the inside. It flows like squeezing. The molten resin flows from the throttle channel portion 19 into the hot water flow channel portion 20 and is filled, and flows out from the hot water flow channel portion 20 to the throttle flow channel portion 21. The molten resin flows so as to constrict a circle from the outside to the inside of the throttle channel portion 21 and reaches almost the same circumference around the gate 22 as shown in FIG. Then, the molten resin flows from the gate 22 to the entire outer periphery of the component molding portion 31.

  Since the opening portion 36 of the overhang forming portion 33 is smaller than the grip forming portion 34 and the hot water flow passage portion 35, the component forming portion 31 has a high viscosity of molten resin before flowing into the overhang forming portion 33. 34 and the whole hot water flow path 35 are filled and filled. At this time, since the gate 22 is provided at the center of the outer peripheral surface of the grip forming part 34 and the hot water flow path part 35, the molten resin can easily spread to every corner of the grip molding part 34 and the hot water flow path part 35. When the filling is completed, the molten resin filled in the gripping molding part 34 and the hot water flow path part 35 flows out to the bulging molding part 33 as shown in FIG. At this time, the molten resin is adjusted so that the flow rate is uniform in the circumferential direction, and flows so as to constrict the circle toward the center of the component molding portion 31, and as shown in FIG. The outer circumference of the part 32 is reached almost simultaneously. The molten resin flows from the entire outer periphery of the main body molding portion 32 toward the center of the component molding portion 31 and is filled in the main body molding portion 32 as shown in FIG.

  When the filling of the molten resin into the component molding part 31 is completed as described above, the mold 1 is cooled. When the molten resin is solidified, as shown in FIG. 1, the mold 1 is opened, and the molded product 7 is pushed out from the movable mold 3 with an ejector pin (not shown). At this time, the molded product 7 is taken out by pressing the positions corresponding to the first connection runner portions 14a, 14b and the second connection runner portions 16a-16d of the second runner portions 15a, 15b with ejector pins (not shown). Therefore, the molded product 7 is pushed out from the gate 22 with a uniform force in the circumferential direction, and the annular seal member 50 is not twisted or warped when taken out.

  By the way, the molded product 7 taken out from the mold 1 is also attached to the outer side of the annular seal member 50 filled with the runner 11 and the sprue 6. Therefore, the molded product 7 is cut at a position between the gate 22 and the component molding unit 31, and the annular seal member 50 is separated from the molded product 7. Thereby, a series of manufacturing steps of the annular seal member 50 is completed.

<Effect>
As described above, in the cylindrical part manufacturing method and the cylindrical part manufacturing die 1 of this embodiment, the molten resin is supplied to the hot water supply part 17 provided in an annular shape along the outside of the part forming part 31. Since the molten resin is evenly flowed from the hot water supply portion 17 to the outside of the component molding portion 31 and filled, the molten resin flows from the outside to the inside of the component molding portion 31 so as to constrict the circle. . Therefore, in the component molding part 31, there is no place where the tip portions of the molten resin that have flowed in two directions merge, and no weld line is generated in the annular seal member 50 molded by the component molding part 31. In addition, since the gate 22 is provided outside the component molding portion 31 and the molten resin is supplied, the gate cut mark does not remain on the inner peripheral surface of the annular seal member 50. Further, due to the flow path structure of the mold 1 that uniformly supplies the molten resin from the outside of the part molding part 31, a weld line is generated in the annular seal part 50, and a gate cut is formed on the inner peripheral surface of the annular seal member 50. Since the generation of traces is prevented, it is not necessary to perform troublesome cutting to remove weld lines and gate cut traces, and the annular seal member 50 can be manufactured at low cost.

  In particular, the molten resin supplied to one input runner portion 12 is evenly distributed to the first runner portion 13, the first connection runner portions 14a and 14b, the second runner portions 15a and 15b, and the second connection runner portions 16a to 16d. Since the molten resin is filled into the hot water supply portion 17 so as to be uniform in the circumferential direction of the hot water supply portion 17 by being divided and supplied to the hot water supply portion 17, It is easy to extrude the molten resin evenly to the outside. In addition, the flow rate of the molten resin is reduced from the hot water circulating portion 17 to the component molding portion 31 by the communication portion 18 so that the molten resin reaches the outside of the component molding portion 31 almost simultaneously. Since the molten resin is flowed from the outside to the inside at a uniform speed over the entire circumference to fill the component molding portion 31 with the molten resin, no weld line is generated.

  Then, the annular seal member 50 is separated from the molded product 7 by cutting the molded product 7 taken out from the mold 1 at a position between the gate 22 and the component molding part 31. Gate cut marks remain on the surface in a ring shape, and it can be easily determined whether or not it is manufactured using the manufacturing method and the mold 1 of the present embodiment.

  Since the annular seal member 50 manufactured in this way does not generate a weld line on the sealing surface, even when a highly penetrating chemical solution flows through the first and second parts 61 and 71, the chemical solution passes through the weld line. There is no leakage outside. Further, since the annular seal member 50 has no irregularities due to the gate cut trace on the inner peripheral surface forming the flow path surface, when the fluid flows along the inner peripheral surface of the annular seal member 50, the gate cut trace on the inner peripheral surface is obtained. As a result, turbulent flow and stagnation do not occur, and fluid replacement and cleanliness are improved.

(Second Embodiment)
Next, a second embodiment of the present invention will be described with reference to the drawings. FIG. 14 is a conceptual diagram of the molten metal flow path 81. FIG. 15 is a DD cross-sectional view of FIG. 16 is a cross-sectional view taken along the line EE in FIG. 17 is a cross-sectional view of the FF in FIG.
In the second embodiment, the configuration is the same as that of the first embodiment except that the communication portion 83 of the runner 82 is different from the communication portion 18 of the first embodiment. Therefore, here, it demonstrates centering on the difference from 1st Embodiment, attaches | subjects the code | symbol same as 1st Embodiment to a common structure, and abbreviate | omits description suitably.

  As shown in FIG. 14, in the molten metal flow path 81, the communication portion 83 of the runner 82 is provided radially between the inside of the hot water circulating portion 17 and the outside of the component molding portion 31. The communication part 83 is provided at equal intervals in the circumferential direction, and is provided apart from each of the second connection runner parts 16a to 16d by the same distance. The molten resin flows evenly to the outside of 31. The communication portion 83 shown in FIGS. 15 to 17 has a circular cross section of the flow path so that the molten resin can easily flow, and the flow path diameter is equal to the flow diameter of the hot water supply section 17 and the hot water supply flow path section 35. The flow rate can be adjusted by narrowing the molten resin flowing from the hot water supply part 17 to the part molding part 31 smaller than the flow path width. In such a runner 82, gates 84 for supplying the molten resin from the communication portion 83 to the hot water circulating portion 17 are opened at equal intervals in the circumferential direction outside the hot water circulating portion 17.

18 and 19 are diagrams for explaining the flow of the molten resin. The dot portion in the figure indicates the region where the molten resin has flowed.
As shown in FIG. 18, when the molten resin is uniformly filled in the entire hot water circulating portion 17, the molten resin is squeezed out to each communicating portion 83 by the pressure of the subsequent molten resin. Since the communication parts 83 are provided at equal intervals in the circumferential direction and are separated from the second connection runner parts 16 a to 16 d by the same distance, the molten resin flows evenly to the communication parts 83. Although the communication part 83 opens intermittently outside the part molding part 31, since the communication part 83 is provided evenly in the circumferential direction, the molten resin is molded from the gate 84 to the part as shown in FIG. Evenly flows into the part 31. Since the overhang forming portion 33 is provided so as to reduce the flow rate, the molten resin flows in a uniform manner by flowing around the grip forming portion 34 and the hot water flow passage portion 35 that have a large flow path cross-sectional area and are easy to flow. After that, it is squeezed out to the overhang forming portion 33 and flows to the outside of the main body forming portion 32. The molten resin flows from the outside of the main body molding portion 32 toward the center portion, and is uniformly filled in the main body molding portion 32. When the component molding part 31 is filled with molten resin and cooled, the mold is opened and the molded product is taken out. Then, the molded product is cut at a position between the component molding unit 31 and the gate 84, and the annular seal member 50 is separated from the molded product.

  Therefore, in the cylindrical part manufacturing method and the cylindrical part manufacturing die according to the present embodiment, the molten resin is caused to flow uniformly from the hot water supply part 17 to the part molding part 31 by the communication part 83 provided in a radial manner. Since the molten resin flows from the outside to the inside of the molding part 31 and fills the part molding part 31, no weld line is generated in the annular sealing member 50 molded by the part molding part 31. In addition, a gate cut mark cut between the gate 84 and the part forming portion 31 remains on the outer peripheral surface of the annular seal member 50. Therefore, the annular seal member 50 is attached to the connection part of the first and second parts 61 and 71 so that the inner peripheral surface forms a part of the flow path, and the highly permeable chemical solution is supplied to the first and second parts 61. , 71 does not leak to the outside through the weld line. Further, since the inner peripheral surface of the annular seal member 50 is not uneven due to the gate cut trace, the fluid flowing along the inner peripheral surface of the annular seal member 50 is free from turbulence and stagnation. Is good. Moreover, the flow path structure of the molten metal flow path 81 prevents a weld line from being generated on the seal surface of the annular seal member 50 and a gate cut mark from remaining on the inner peripheral surface of the annular seal member 50. The operation of removing lines and gate cut marks is not required, and the annular seal member 50 can be manufactured at low cost.

  In addition, since the gate cut marks cut at the position between the gate 84 and the part molding portion 31 remain at regular intervals on the outer peripheral surface of the annular seal member 50, the outer peripheral surface of the annular seal member 50 is If it sees, it can discriminate | determine easily whether it was manufactured using the manufacturing method and metal mold | die of this embodiment.

In addition, this invention is not limited to the said embodiment, Various application is possible.
For example, in the above embodiment, the resin annular seal member 50 is taken as an example of an annular component. However, the manufacturing method and the mold of the above embodiment are also used for manufacturing an annular component such as a cylindrical lens frame. it can.
For example, in the above-described embodiment, the annular seal member 50 is provided with the projecting portion 52 and the grip portion 53 on the main body portion 51 so that the annular seal member 50 can be easily attached to the first and second connection portions 62 and 72. An annular seal member including only the main body 51 may be used. The annular seal member including only the main body 51 is disposed at a connection portion between the valve main body and the cylinder of the valve, a connection portion of a connection pipe or a connection block, or the like.
For example, in the above embodiment, a molten resin such as a fluororesin is used as the molten metal, but a molten metal may be used as the molten metal.

DESCRIPTION OF SYMBOLS 1 Mold for cylindrical part manufacture 7 Molded article 10 Molten flow path 11, 82 Liner 12 Input runner part 13 1st runner part 14a, 14b 1st connection runner part 15a, 15b 2nd runner part 16a-16d 2nd connection runner Portion 17 Hot-water supply portion 18, 83 Communication portion 22, 84 Gate 31 Component molding portion 50 Annular seal member (an example of cylindrical component)
61 1st part 63 1st annular seal groove 71 2nd part 73 2nd annular seal groove

Claims (6)

In a cylindrical part manufacturing method for manufacturing a cylindrical part using a mold having a molten metal flow path for supplying a molten metal from a runner to a part molding part through a gate,
Said along the outside of the part-forming portion filled by supplying the molten metal to the molten metal around portion provided on annular, filled by flowing a molten metal filled in the hot water around portion from the outer peripheral side of the part-forming portion ,
After being supplied to the input runner portion of the runner, the molten metal is diverted through the first runner portion at a first connection runner portion provided symmetrically with respect to the input runner portion as a reference, and the first runner portion. Through the second runner portion on the inner side of the first connection runner portion, the second connection runner portion provided at a symmetric position and at intervals of 90 degrees with respect to the first connection runner portion. A method for manufacturing a cylindrical part, characterized in that the molten metal is supplied at regular intervals in the direction, and the molten metal is evenly supplied from the hot water supply part to the part forming part in the circumferential direction . In the manufacturing method of the cylindrical component of Claim 1 ,
A communication part is provided in an annular shape between the inside of the hot water part and the outside of the part molding part, the flow rate of the molten metal flowing from the hot water part to the communication part is reduced, and the part molding part is connected from the communication part. The molten metal is supplied from the outside of the cylindrical part. In the manufacturing method of the cylindrical component of Claim 1 ,
A communicating part is radially provided between the inside of the hot water part and the outside of the part molding part, and the hot water part is connected to the part molding part at equal intervals in the circumferential direction. A method of manufacturing a cylindrical part, wherein the molten metal is supplied from the outside of the component molding part from the communication part by reducing the flow rate of the molten metal flowing to the communication part. Used for manufacturing a cylindrical part having a cylindrical shape, a part molding part corresponding to the cylindrical part, a runner for flowing a molten metal to the part molding part, and a gate for supplying the molten metal from the runner to the part molding part In a mold for manufacturing a cylindrical part having
The runner is
An annular hot water portion provided concentrically with the component molding portion on the outside of the component molding portion;
A communicating portion for communicating the inside of the hot water circulating portion and the outside of the component molding portion;
Having a runner portion for filling the molten metal in the hot water portion ,
The runner portion is
One input runner for inputting the molten metal;
A first runner section that flows through the molten metal supplied from the input runner section;
A first connection runner portion that is provided 180 degrees symmetrically with respect to the input runner portion;
A second runner portion provided inside the first runner portion and flowing through the molten metal supplied from the first connection runner portion;
Diverting the molten metal flowing in the second runner portion, second connection runner portions provided at symmetrical positions and at intervals of 90 degrees with respect to the first connection runner portion;
A mold for manufacturing a cylindrical part, wherein the mold is connected in a circumferential direction with respect to the hot water circulating portion . In the cylindrical part manufacturing mold according to claim 4 ,
In the communication portion, the outer opening width that opens to the hot water portion is smaller than the flow width of the hot water portion, and the inner opening width that opens to the component molding portion is the flow width of the outer periphery of the component molding portion. A mold for manufacturing cylindrical parts characterized by being smaller. In the cylindrical part manufacturing mold according to claim 5 ,
The mold for manufacturing a cylindrical part, wherein the communication part is provided annularly or radially between the hot water circulating part and the part molding part.

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