200402357 Π) 玖、發明說明 【發明所屬之技術領域】 本發明是關於脫蠟鑄造用的射出成型裝置以及射出成 型方法，特別是關於珠寶飾品的製造所使用的脫鱲鑄造用 的射出成型裝置以及射出成型方法。 【先前技術】 在珠寶飾品的製造中如以下的脫蠟鑄造常被使用。即 在埋入母模（master pattern)於鑄模（mold)中加硫後，切開 鑄模取出母模，在取出母模後的鑄模內的空洞（模樣 ^pattern)射出低熔點蠟，組合所得到的蠟模爲樹狀而形成 石膏鑄模，藉由在爐中升溫此石膏鑄模使鱲燃燒以及蒸發 ，在燃燒以及蒸發的結果形成的石膏鑄模的空洞內注入熔 融金屬，以製造像母模的鑄造物。在這種脫蠟鑄造中，因 母模的形狀複雜故常使用橡膠鑄模。 在使用習知的橡膠鑄模的脫蠟鑄造中，有因射出後的 蠟的收縮使成型品對預定的形狀凹陷或產生縮陷 (depression)的所謂的縮孔（shrinkage)的狀態容易發生的 問題點。此點對於壁厚的模樣的橡膠鑄模的情形特別顯著 〇 爲了改善此縮孔，估計蠟的收縮提高對應預先射出供 給多一些量的蠟之橡膠鑄模的低熔點蠟的射出壓（射出壓 力），且保持此高的射出壓的方法被進行。但是在藉由高 的射出壓供給鱲的此方法中，因橡膠鑄模爲了取出母模而 -5- (2) (2)200402357 切開，故若繼續施加高的射出以射出蠟的話，在橡膠鑄模 的切口及其週邊會容易產生毛邊。而且，因以高的射出壓 來射出，故有在蠟模內發生空化現象（cavitation)，容易與 鑄造後的蠟模的品質的降低有關。 【發明內容】 因此，本發明的目的爲提供在藉由珠寶飾品的製造所 使用的具有彈性的鑄模的脫蠟鑄造中，可抑制因成型品的 收縮造成毛邊、縮孔、空化現象的發生，得到所希望的形 狀、重量的高品質的蠟模的射出成型裝置以及射出成型方 法。而且，本發明的目的爲抑制成型品的收縮。 本發明的上述以外的目的以及本發明的特徵藉由參照 添附圖面且閱讀以下的詳細的說明而更明確。 爲了解決上述課題，在本發明的脫蠟鑄造用的射出成 型裝置或脫蠟鑄造用的射出成型方法中，藉由射出成型機 在鑄模的內部射出熱熔融性物質的射出壓爲射出開始時爲 第一射出壓，令在由射出開始預定時間後比第一射出壓還 大爲第二射出壓。 【實施方式】 以下，參照圖面詳細地說明與本發明有關的實施例。 第1圖是顯示構成實施例的脫蠘鑄造用射出成型裝置 的蠟射出器（wax injector) 1以及輸入裝置20的槪要的立體 圖。第2圖是顯不實施例的槽（tank)2與閥（valve)3的關連 (3) (3)200402357 的立體圖。第3圖是由第2圖的III方向看實施例的閥3時 的剖面圖。第4圖是顯示構成實施例的脫蠟鑄造用射出成 型裝置的一部分的自動夾具（auto clamp)30的槪要的側面 圖。第5圖是顯示實施例的射出時間與射出壓力（射出壓） 的關係圖。 實施例的脫蠟鑄造用射出成型裝置是由蠟射出器（射 出成型機）1、輸入裝置20、自動夾具3 0等構成。以下說明 其詳細。 蠟射出器1是在內部具有：儲存具有以65 °C左右的溫度 熔解的特性的蠟（熱熔融性物質）用的槽（蠟槽）2，與熔解蠟 ，保持於熔融狀態且具有維持於最適當的射出溫度用的溫 度控制功能的閥3。 槽2是在內部貯藏蠟，藉由具有密封構件（未圖示）的 蓋4密封。槽2的內部可藉由壓縮氣體加壓。在槽2內部具 備內部被保持於比大氣壓還相當低的壓力，且使蠟不侵入 的真空槽5。因此’蠟被貯藏於槽2內部真空槽5的外側。 閥3在相面對的側面互相獨立地具有真空閥6與射出閥 7的兩個閥。真空閥6可藉由對真空閥6驅動用的電磁線圈8 通電而開放，射出閥7可藉由對射出閥7驅動用的電磁線圈 9通電而開放。真空閥6連通到真空槽5，射出閥7經由蠟射 出管10連通到槽2。在閥3的再其他側面係使加熱器η與射 出噴嘴12面對而配設。射出噴嘴12可在其前端部分使橡膠 鑄模（具有彈性的鑄模（彈性鑄模））13密接。 此處’具有彈性的鑄模（彈性鑄模）係指在射出壓中鑄 -7- (4) (4)200402357 模進行彈性內的變形、復原的鑄模，例如有橡膠製的鑄模 〇 輸入裝置20連接於射出成型機，在其上面具備液晶畫 面2 1以及按鈕2 2。藉由操作按鈕2 2可設定變更射出壓、總 射出時間、每一射出壓的射出時間、槽2內的蠟溫度、射 出噴嘴12的溫度、射出噴嘴12的排氣時間（真空時間）、鑄 模按壓壓力（鑄模壓力）、鑄模保持時間、橡膠鑄模1 3的種 類、橡膠鑄模1 3的批號等的資訊（射出條件）。此處，橡膠 鑄模13的種類是藉由橡膠鑄模13形成的蠟模的模樣的壁厚 、外形尺寸、蠟的種類而定。 自動夾具30是在蠟射出器1的射出噴嘴12的正面經由 底座（base)31固定於作業台（未圖示）。在底座31上搭載橡 膠鑄模13用的台（stage)32係經由前進用氣缸33而配置。台 32因固定於前進用氣缸33，故藉由前進用氣缸33的水平方 向的動作使台32可在水平方向移動。而且，在台32的上方 配置夾具氣缸34。在夾具氣缸34的底面配設有平板 (plate)35，藉由夾具氣缸34的鉛直方向的動作使搭載於台 3 2上的橡膠鑄模13被台32與平板35夾住保持。在如此構成 的自動夾具3 0中，在保持橡膠鑄模1 3的狀態下台3 2前進到 蠟射出器1側，可使配設於橡膠鑄模1 3的一側面的澆道 (sprue)14與射出噴嘴12密接。 在如以上構成的本實施例的蠟射出器1中，在藉由自 動夾具30使橡膠鑄模13的內部通過澆道連通於閥3而裝設 於射出噴嘴12的狀態下，若藉由對真空閥6驅動用的電磁 (5) (5)200402357 線圈通電而打開真空閥6的話，閥3因與真空槽5連接，故 射出噴嘴12的內部以及通過射出噴嘴12而連通的橡膠纟壽| 莫 13內部的空隙15被排氣。另一方面，在關閉真空閥6後， 藉由對閥驅動用的電磁線圈通電而打開射出閥7的話，g 射出閥7、蠟射出管10以及槽2連通，故槽2內的熔融蠘透 過射出噴嘴12藉由槽2內的加壓氣體得到射出能量，射& 到橡膠鑄模13內部的空隙。 在本實施例中，爲了形成最大壁厚1mm的模樣用的 橡膠鑄模13，如以下設定條件。 第一射出壓（射出開始時的射出壓）：〇.3kg/cm3 第一射出壓的保持時間：1秒 第二射出壓：〇.6kg/cm3 第二射出壓的保持時間：1〇秒 總射出時間秒 槽2內的蠟溫度：70t 射出噴嘴12的溫度：68°C 射出噴嘴12的排氣時間（真空時間）：2秒 橡膠鑄模13壓力：5kg/cm3 保持時間：5秒 此處，射出時間與射出壓成爲第5圖所示的關係，橡 膠鑄模13內部僅預定的保持時間被維持於第一射出壓，然 後射出壓被切換到第二射出壓，僅預定的保持時間以第二 射出壓維持。在這種射出條件之下，對在以5kg/cm3按壓 的狀態下排氣2秒鐘而內部變成真空的橡膠鑄模1 3，在槽2 (6) (6)200402357 內以及射出噴嘴12內射出被保持於68 °C的蠟。射出開始時 的射出壓爲第一射出壓〇·3 kg/cm3，以此射出壓射出1秒鐘 後更以第二射出壓〇·6 kg/cm3進行10秒鐘射出（總射出時間 11秒）後關閉射出閥7，完成射出。因此，射出完成時的射 出壓爲第二射出壓0.6 kg/cm3。然後，以自動夾具30保持 橡膠鑄模13五秒鐘後，打開藉由自動夾具30的保持，由橡 膠鑄模13取出蠟模。 一般，若以預定値以上的射出壓朝橡膠鑄模13內射出 蠟的話，具有彈性的橡膠鑄模13會藉由被加壓的蠟而被擴 張。再者，因若增大射出壓的話，在橡膠鑄模13的切口蠟 會進入，故毛邊容易產生。 相對於此在本實施例中，如以下進行射出。首先，以 不擴張橡膠鑄模13程度的相當低壓的第一射出壓在橡膠鑄 模13內射出供給蠟。此時，僅預定的保持時間保持於第一 射出壓。因令第一射出壓爲不擴張橡膠鑄模13程度的相當 低壓，故以第一射出壓射出到橡膠鑄模13內的蠟不擴張橡 膠鑄模13而在橡膠鑄模13內相當地蔓延。因此，可避免藉 由擴張橡膠鑄模13在橡膠鑄模13的切口蠟會進入，毛邊產 生的可能性。此處，第一射出壓的前述預定的保持時間是 令以第一射出壓射出的蠟之中與橡膠鑄模1 3內面接觸的表 面層凝固程度的時間。如此因確保與橡膠鑄模1 3內面接觸 的表面層凝固程度的時間，故在第一射出壓的預定的保持 時間經過後，即使以更高壓的第二射出壓進行射出因凝固 的蠟表面層與橡膠鑄模1 3內面接觸，故即使有橡膠鑄模1 3 •10- (7) (7)200402357 被擴張’在橡膠鑄模13的切口蠟會進入而毛邊產生的可能 性也低。 因此’在以第一射出壓對橡膠鑄模1 3內供給鱲後，更 以擴張橡膠鑄模1 3程度的高的壓力之第二射出壓進行蠟的 射出供給。以第二射出壓中的蠟的射出供給係在橡膠鑄模 1 3內補充蠟收縮的體積份。因此，可抑制成型品的收縮， 據此，在第二射出壓的保持時間終了前進行蠟的凝固，即 使澆道14的部分的蠟完全凝固，因對橡膠鑄模13以第二射 出壓使估計收縮的蠟被供給，故可得到所希望的形狀、重 量的蠟模。 在藉由以低的第一射出壓進行一定時間射出後，更以 比第一射出壓還高的第二射出壓進行一定時間射出，無成 型品的收縮、毛邊、空化現象的發生，可得到所希望的形 狀、重量的高品質的蠟模。 在上述實施例中，雖然令第一射出壓爲〇.3kg/cm3， 第二射出壓爲0.6kg/cm3，惟若第二射出壓比第一射出壓 還大，且在〇〜2 kg/cm3的範圍內的話，都能設定於第一射 出壓以及第二射出壓的任一値。 在上述實施例中，雖然令射出壓爲第一射出壓、第二 射出壓的階梯（step)狀的兩階段，但令三階段以上的階梯 狀的射出壓也可以。再者，不保持射出壓一定時間而連續 地增加也可以。而且，以組合階梯狀的增加與連續的增加 的形式給予射出壓也可以。 而且，即使在階梯狀或/及連續地使射出壓變化的情 -11 - (8) (8)200402357 形的任一種，在給予預定的射出壓開始射出後，若給予比 射出開始時的射出壓還大的射出壓的話，在射出中或射出 終了時使射出壓減少也可以。 在上述實施例中，雖然令第一射出壓的保持時間爲1 秒，第二射出壓的保持時間爲10秒，惟任一射出壓均可在 0〜20秒之間設定。 在上述實施例中，雖然使用橡膠製的鑄模，惟若可藉 由以預定的射出壓射出在鑄模內加壓蠟而擴張鑄模的話， 鑄模所使用的材料爲橡膠以外也可以。即若使用以剛體以 外的材料製作的鑄模的話，可期待完成與上述實施例一樣 的功效。 在上述實施例中，雖然使用真空槽5對射出噴嘴1 2 的內部以及橡膠鑄模13的內部的空隙15排氣，但省略真空 槽5不進行空隙1 5的排氣而進行射出也可以。 依照橡膠鑄模13的種類，預先將射出壓、總射出時間 、每一射出壓的射出時間、槽2內的蠟溫度、射出噴嘴1 2 的溫度、射出噴嘴12的排氣時間（真空時間）、橡膠鑄模13 按壓壓力（鑄模壓力）、保持時間等的資訊（射出條件）記憶 於輸入裝置20、個別的記憶裝置或射出機也可以。 藉由對輸入裝置20、個別的記憶裝置或射出機依次輸 入射出壓、射出總時間、每一射出壓的射出時間等的資訊 ，也能作成、記憶依照預先設定的條件自動地進行射出的 射出程式。而且，藉由對輸入裝置20的各個按鈕分配每一 橡膠鑄模13的種類的程式，也能以單觸（one touch)設定射 200402357 Ο) 出條件。再者，藉由對各個按鈕分配射出壓等的資訊，也 能在射出中以單觸變更射出條件。 在上述實施例中’雖然是關於珠寶飾品的製造所使用 的脫獵繪造用的射出成型裝置以及射出成型方法，惟本發 明並非限定於珠寶飾品的製造用的脫鱲鑄造。 雖然針對本發明參照上述實施例來說明，惟本發明並 非限定於上述實施例，在改良的目的或本發明的思想的範 圍內改良或變更爲可能。 如以上所說明的’如果依照本發明在珠寶飾品的製造 所使用的脫蠟鑄造中，可提供抑制毛邊、縮孔、空化現象 的發生以及成型品的收縮，可得到所希望的形狀的高品質 的蠟模的射出成型裝置以及射出成型方法。 以上的說明是顯示較佳的實施形態，所謂的熟習該項 技術者可想到的範圍中的發明的改變係包含於本案發明。 本案發明的技術範圍是由申請專利範圍決定。 【圖式簡單說明】 第1圖是顯示構成實施例的脫蠟鑄造用射出成型裝置 的蠟射出器1以及輸入裝置20的槪要的立體圖。 第2圖是顯示實施例的槽2與閥3的關連的立體圖。 第3圖是由第2圖的III方向看實施例的閥3時的剖面 圖。 第4圖是顯示構成實施例的脫蠟鑄造用射出成型裝置 的一部分的自動夾具30的槪要的側面圖。 (10)200402357 第5圖是顯示實施例的射出時間與射出壓力的關係圖 【符號說明】200402357 Π) 发明 Description of the invention [Technical field to which the invention belongs] The present invention relates to an injection molding device and an injection molding method for dewaxing casting, and more particularly, to an injection molding device for dewaxing casting used in the manufacture of jewelry and Injection molding method. [Prior art] In the manufacture of jewelry, the following dewaxing casting is often used. That is, after burying a master pattern in a mold and adding sulfur, the mold is cut open to take out the master mold, and the low-melting wax is injected into the cavity (pattern) in the mold after the master mold is taken out. The wax mold is tree-shaped to form a gypsum mold. The gypsum mold is heated and heated in a furnace to burn and evaporate the urn. The molten metal is injected into the cavity of the gypsum mold formed as a result of the combustion and evaporation to produce a casting like a master mold. . In this dewaxing casting, a rubber mold is often used because the shape of the master mold is complicated. In the dewaxing casting using a conventional rubber mold, there is a problem that a state of a so-called shrinkage in which a molded article is dented to a predetermined shape or a depression occurs due to shrinkage of the wax after injection is problematic. point. This is particularly significant in the case of rubber molds with wall thickness patterns. In order to improve the shrinkage, it is estimated that the shrinkage of the wax increases the injection pressure (injection pressure) of the low-melting wax that corresponds to the rubber mold injecting more wax in advance. And a method of maintaining this high injection pressure is performed. However, in this method of supplying osmium with a high injection pressure, the rubber mold is cut in order to remove the mother mold -5- (2) (2) 200402357. Therefore, if a high injection is continued to be applied to inject wax, The cuts and their surroundings are prone to burrs. In addition, since injection is performed at a high injection pressure, cavitation occurs in the wax mold, which is likely to be related to the deterioration of the quality of the wax mold after casting. [Summary of the Invention] Therefore, an object of the present invention is to provide a method for suppressing occurrence of burrs, shrinkage, and cavitation due to shrinkage of a molded article in dewaxing casting having a flexible mold used in the manufacture of jewelry. To obtain a high-quality wax mold injection molding device and injection molding method with a desired shape and weight. Moreover, the objective of this invention is to suppress shrinkage of a molded article. The other objects of the present invention and the features of the present invention will become clearer by referring to the attached drawings and reading the following detailed description. In order to solve the above-mentioned problems, in the injection molding apparatus or the injection molding method for dewax casting of the present invention, the injection pressure of the hot-melt substance inside the mold by the injection molding machine is set to be at the start of injection The first injection pressure is set to be greater than the first injection pressure to a second injection pressure after a predetermined time from the start of injection. [Embodiment] Hereinafter, embodiments related to the present invention will be described in detail with reference to the drawings. Fig. 1 is a schematic perspective view showing a wax injector 1 and an input device 20 constituting the injection molding apparatus for sintering casting according to the embodiment. Fig. 2 is a perspective view showing the relationship between the tank 2 and the valve 3 of the embodiment (3) (3) 200402357. Fig. 3 is a sectional view when the valve 3 of the embodiment is viewed from the III direction in Fig. 2. Fig. 4 is a schematic side view showing an automatic clamp 30 constituting a part of the injection molding apparatus for dewaxing casting of the embodiment. Fig. 5 is a graph showing the relationship between the injection time and the injection pressure (injection pressure) in the embodiment. The injection molding apparatus for dewaxing casting in the embodiment is composed of a wax injector (injection molding machine) 1, an input device 20, an automatic jig 30, and the like. The details are described below. The wax ejector 1 is internally provided with a tank (wax tank) 2 for storing wax (heat-meltable substance) having a characteristic of melting at a temperature of about 65 ° C, and a molten wax, which is maintained in a molten state and maintained at Temperature control function valve 3 for optimum injection temperature. The tank 2 stores wax therein, and is sealed by a lid 4 having a sealing member (not shown). The inside of the tank 2 can be pressurized by compressed gas. Inside the tank 2, there is a vacuum tank 5 in which the inside is kept at a pressure lower than the atmospheric pressure and the wax does not enter. Therefore, the 'wax is stored outside the vacuum tank 5 inside the tank 2. The valve 3 includes two valves of a vacuum valve 6 and an injection valve 7 independently of each other on opposite sides. The vacuum valve 6 can be opened by energizing the electromagnetic coil 8 for driving the vacuum valve 6, and the injection valve 7 can be opened by energizing the electromagnetic coil 9 for driving the injection valve 7. The vacuum valve 6 communicates with the vacuum tank 5, and the injection valve 7 communicates with the tank 2 through the wax injection pipe 10. On the other side of the valve 3, the heater? Is disposed so as to face the ejection nozzle 12. The injection nozzle 12 can closely contact a rubber mold (a mold having elasticity (an elastic mold)) 13 at a front end portion thereof. Here, the "elastic mold (elastic mold)" refers to a mold that is deformed and restored within the elasticity when the injection mold -7- (4) (4) 200402357 is used. For example, there is a rubber mold. The injection molding machine includes a liquid crystal screen 21 and buttons 22 on the upper surface. The operation button 22 can be set to change the injection pressure, the total injection time, the injection time for each injection pressure, the wax temperature in the tank 2, the temperature of the injection nozzle 12, the exhaust time (vacuum time) of the injection nozzle 12, and the mold. Information on the pressing pressure (mold pressure), mold holding time, type of rubber mold 13 and batch number of rubber mold 13 (injection conditions). Here, the type of the rubber mold 13 is determined by the wall thickness, the external dimensions, and the type of the wax pattern of the wax mold formed by the rubber mold 13. The automatic jig 30 is fixed to a work table (not shown) on the front surface of the injection nozzle 12 of the wax ejector 1 via a base 31. A stage 32 on which the rubber mold 13 is mounted on the base 31 is arranged via a cylinder 33 for advancing. Since the table 32 is fixed to the forward cylinder 33, the horizontal movement of the forward cylinder 33 allows the table 32 to move in the horizontal direction. A jig cylinder 34 is disposed above the stage 32. A plate 35 is arranged on the bottom surface of the clamp cylinder 34, and the rubber mold 13 mounted on the stage 32 is clamped and held by the stage 32 and the plate 35 by the vertical movement of the clamp cylinder 34. In the automatic jig 30 configured as described above, the stage 32 is advanced to the side of the wax ejector 1 while the rubber mold 13 is held, and the sprue 14 and the injection disposed on one side of the rubber mold 13 can be made. The nozzle 12 is in close contact. In the wax ejector 1 of the present embodiment configured as described above, in a state where the inside of the rubber mold 13 is connected to the valve 3 through a runner and installed in the injection nozzle 12 by the automatic clamp 30, if the vacuum Solenoid for driving valve 6 (5) (5) 200 402 357 When the coil 6 is turned on and the vacuum valve 6 is opened, the valve 3 is connected to the vacuum tank 5, so the inside of the injection nozzle 12 and the rubber that communicates through the injection nozzle 12 | Mo The void 15 inside 13 is exhausted. On the other hand, after the vacuum valve 6 is closed and the injection valve 7 is opened by energizing the solenoid for driving the valve, the g injection valve 7, the wax injection tube 10, and the tank 2 communicate with each other, so that the molten plutonium in the tank 2 permeates. The injection nozzle 12 obtains injection energy from the pressurized gas in the tank 2 and shoots into a space inside the rubber mold 13. In this embodiment, in order to form a rubber mold 13 for a pattern having a maximum wall thickness of 1 mm, conditions are set as follows. First injection pressure (injection pressure at the start of injection): 0.3 kg / cm3 Holding time of the first injection pressure: 1 second Second injection pressure: 0.6 kg / cm3 Holding time of the second injection pressure: 10 seconds Total Injection time Wax temperature in slot 2: 70t Temperature of injection nozzle 12: 68 ° C Exhaust time (vacuum time) of injection nozzle 12: 2 seconds Rubber mold 13 Pressure: 5kg / cm3 Holding time: 5 seconds Here, The injection time and the injection pressure have the relationship shown in FIG. 5. Only the predetermined holding time in the rubber mold 13 is maintained at the first injection pressure, and then the injection pressure is switched to the second injection pressure. Only the predetermined holding time is changed to the second injection pressure. Injection pressure is maintained. Under this injection condition, the rubber mold 1 3, which has been evacuated for 2 seconds while being pressurized at 5 kg / cm3, is turned into a vacuum, and is injected into the groove 2 (6) (6) 200402357 and the injection nozzle 12 Wax kept at 68 ° C. The injection pressure at the start of injection is the first injection pressure 0.3 kg / cm3, and the injection pressure is 1 second and the injection pressure is 0.6 kg / cm3 for 10 seconds (the total injection time is 11 seconds). ) Close the injection valve 7 to complete the injection. Therefore, the injection pressure when the injection is completed is the second injection pressure of 0.6 kg / cm3. Then, after holding the rubber mold 13 with the automatic jig 30 for five seconds, the holding of the automatic mold 30 was opened, and the wax mold was taken out from the rubber mold 13. In general, if the wax is injected into the rubber mold 13 at a predetermined injection pressure or more, the rubber mold 13 having elasticity is expanded by the pressurized wax. Furthermore, if the injection pressure is increased, the cut wax in the rubber mold 13 will enter, so that burrs are likely to occur. In contrast, in this embodiment, injection is performed as follows. First, a relatively low first injection pressure that does not expand the rubber mold 13 is injected into the rubber mold 13 to supply wax. At this time, only the predetermined holding time is maintained at the first injection pressure. Because the first injection pressure is a relatively low pressure that does not expand the rubber mold 13, the wax injected into the rubber mold 13 at the first injection pressure does not expand the rubber mold 13 and spreads considerably in the rubber mold 13. Therefore, it is possible to avoid the possibility that the cut wax in the rubber mold 13 may enter due to the expansion of the rubber mold 13 and burrs may be generated. Here, the aforementioned predetermined holding time for the first injection pressure is a time for the surface layer of the wax injected with the first injection pressure to contact the inner surface of the rubber mold 13 to a degree of solidification. In this way, since the solidification time of the surface layer in contact with the inner surface of the rubber mold 13 is ensured, even after the predetermined holding time of the first injection pressure has elapsed, the wax surface layer due to the solidification is injected even at the second injection pressure of higher pressure. It is in contact with the inner surface of the rubber mold 1 3, so even if the rubber mold 1 3 • 10- (7) (7) 200402357 is expanded, the cut wax in the rubber mold 13 will enter and the possibility of burrs is low. Therefore, after the 鱲 is supplied to the rubber mold 13 with the first injection pressure, the wax is injected and supplied at the second injection pressure with a high pressure of the expansion of the rubber mold 13. The wax injection supply in the second injection pressure is used to replenish the shrinkable volume of wax in the rubber mold 1 3. Therefore, it is possible to suppress the shrinkage of the molded product, and accordingly, the wax is solidified before the holding time of the second injection pressure ends, and even if the wax of the runner 14 is completely solidified, the rubber mold 13 is estimated by the second injection pressure. The shrunken wax is supplied, so that a wax mold having a desired shape and weight can be obtained. After the injection is performed for a certain period of time with a low first injection pressure, the injection is performed for a certain period of time with a second injection pressure that is higher than the first injection pressure. There is no occurrence of shrinkage, burrs, or cavitation of the molded product. A high-quality wax pattern having a desired shape and weight is obtained. In the above embodiment, although the first injection pressure is 0.3 kg / cm3 and the second injection pressure is 0.6 kg / cm3, if the second injection pressure is larger than the first injection pressure, and is between 0 and 2 kg / In the range of cm3, it can be set to any one of the first injection pressure and the second injection pressure. In the above-mentioned embodiment, although the injection pressure is set to two steps of the first injection pressure and the second injection pressure, the step-shaped injection pressure may be three steps or more. Furthermore, the injection pressure may be continuously increased without maintaining the injection pressure for a certain period of time. It is also possible to apply injection pressure in the form of a combination of stepwise increase and continuous increase. In addition, even in the case of step-shaped or / and continuously changing the injection pressure, any of the -11-(8) (8) 200402357 shapes, after the injection is given a predetermined injection pressure, if the injection is given than the injection at the start of injection If the injection pressure is still high, the injection pressure may be reduced during or at the end of the injection. In the above embodiment, although the holding time of the first injection pressure is 1 second and the holding time of the second injection pressure is 10 seconds, any injection pressure can be set between 0 and 20 seconds. Although the rubber mold is used in the above embodiment, if the mold can be expanded by injecting a pressurized wax in the mold at a predetermined injection pressure, the mold may be made of a material other than rubber. That is, if a mold made of a material other than a rigid body is used, the same effects as those of the above embodiment can be expected. In the above-mentioned embodiment, although the vacuum chamber 5 is used to exhaust the inside of the injection nozzle 12 and the space 15 inside the rubber mold 13, the vacuum chamber 5 may be omitted without performing the exhaust of the space 15 to perform the injection. According to the type of the rubber mold 13, the injection pressure, the total injection time, the injection time for each injection pressure, the wax temperature in the tank 2, the temperature of the injection nozzle 12 and the exhaust time (vacuum time) of the injection nozzle 12, The rubber mold 13 may store information (injection conditions) such as pressing pressure (mold pressure) and holding time in the input device 20, an individual memory device, or an injection machine. By sequentially inputting information such as injection pressure, total injection time, and injection time for each injection pressure into the input device 20, an individual memory device, or an injection machine, it is possible to create and memorize injections that are automatically performed according to preset conditions. Program. In addition, by assigning the type of each rubber mold 13 to each button of the input device 20, it is also possible to set the shooting conditions by one touch. Furthermore, by assigning information such as injection pressure to each button, the injection conditions can be changed with one touch during the injection. In the above-mentioned embodiment, although the injection molding device and the injection molding method for hunting and drawing production used in the production of jewelry, the present invention is not limited to the casting casting for the production of jewelry. Although the present invention has been described with reference to the above-mentioned embodiments, the present invention is not limited to the above-mentioned embodiments, and improvements or changes may be made within the scope of the purpose of improvement or the idea of the present invention. As described above, if the dewaxing casting used in the manufacture of jewelry according to the present invention can suppress occurrence of burrs, shrinkage, cavitation, and shrinkage of a molded article, a desired shape can be obtained. High-quality wax mold injection molding device and injection molding method. The above description shows a preferred embodiment, and changes in the invention within the scope conceivable by those skilled in the art are included in the present invention. The technical scope of the invention in this case is determined by the scope of patent application. [Brief Description of the Drawings] Fig. 1 is a perspective view showing essential parts of the wax ejector 1 and the input device 20 constituting the injection molding apparatus for dewaxing casting according to the embodiment. FIG. 2 is a perspective view showing the relationship between the tank 2 and the valve 3 in the embodiment. Fig. 3 is a sectional view when the valve 3 of the embodiment is viewed from the III direction in Fig. 2. Fig. 4 is a schematic side view showing the automatic jig 30 constituting a part of the injection molding apparatus for dewaxing casting of the embodiment. (10) 200402357 Fig. 5 is a graph showing the relationship between the injection time and the injection pressure in the embodiment. [Symbol description]
1:蠟射出器 2：槽 3:閥 4:蓋 5:真空槽 6:真空閥 7:射出閥 8、9 :電磁線圈 10:蠟射出管 11:加熱器 1 2 :射出噴嘴 13:橡膠鑄模 14:澆道 1 5 :空隙 20 :輸入裝置 2 1:液晶畫面 22:按鈕 3 0 :自動夾具 31:底座 32:台 -14· (11)200402357 3 3 :前進用氣缸 34:夾具氣缸 35:平板1: Wax injection device 2: Slot 3: Valve 4: Cover 5: Vacuum tank 6: Vacuum valve 7: Injection valve 8, 9: Solenoid coil 10: Wax injection tube 11: Heater 1 2: Injection nozzle 13: Rubber mold 14: runner 1 5: gap 20: input device 2 1: LCD screen 22: button 3 0: automatic clamp 31: base 32: stage -14 (11) 200402357 3 3: forward cylinder 34: clamp cylinder 35: flat
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