RU2164837C1 - Press-mold for making castings with internal thread with use of investment patterns - Google Patents

Abstract

FIELD: foundry, namely, manufacture of castings with internal thread with use of investment patterns. SUBSTANCE: press-mold includes threaded rod having helical grooves on its lateral surface. Threaded sleeve is mounted in intermediate plate; guiding sleeve is mounted in knocking out unit. Guiding sleeve has pins engaging with helical grooves of rod. When press-mold is open knocking out unit moves relative to threaded rod. Guiding sleeve moves in lengthwise direction and pins drive rod to rotation for unscrewing rod out off casting. EFFECT: enhanced reliability of press-mold, increased accuracy of casting profiled articles, enlarged manufacturing possibilities of press-mold. 1 dwg

Description

The invention relates to foundry, in particular to investment casting molds of castings with internal thread
A known mold for injection molding of castings with internal interrupted thread (A.S. N 531642, B 22 D 17/22, 26.10.76).

 Known press-form contains a movable matrix, a fixed matrix, an intermediate plate, a threaded rod, on the lateral surface of which longitudinal grooves and a copy groove are made, which includes a driving pin located in the ejection unit. The threaded rod in the lower part is equipped with a threaded shank that enters the fixed threaded sleeve, which is located in the ejection block and is fixed from turning. The shank and threaded sleeve are a copy pair.

 However, the known mold is a device in which the copy pair and the forming profile of the rod are disconnected, which in the manufacture of separate elements gives an error and increases the complexity.

 In addition, in the known mold, the thread of the product is an interrupted helix, which reduces the power and operational characteristics of the product.

 Only through threads are possible.

The claimed technical solution is aimed at improving the reliability of the mold, increasing the accuracy of the product profile and power characteristics, as well as expanding the technological capabilities of the mold
For this, a casting mold for investment casting with an internal thread, containing a movable die, a fixed die, an intermediate plate, an ejection block, a threaded rod that engages with a threaded sleeve fixed against rotation, and a pin meshed with a screw the groove made on the lateral surface of the threaded rod is provided with a guide sleeve located in the ejection unit, and an additional pin that engages with an additional screw groove made on b kovoy surface of the threaded rod, the threaded rod is mounted in a guide bushing, the pins are rigidly fixed on the side surface of the guide sleeve and the threaded sleeve is secured in a fixed matrix and fixed against rotation of the intermediate plate.

 The drawing shows a mold in section.

 The investment casting mold for castings with internal thread contains a movable die 1, a fixed die 2, an intermediate plate 3, and an ejection unit consisting of an ejection plate 4 and a pressure plate 5.

 In the stationary matrix 2 is fixed a threaded sleeve 6, fixed from rotation by an intermediate plate 3.

 In the ejection unit, in plates 4 and 5, a guide sleeve 7 is placed with two pins 8 rigidly fixed in its side surface and with a threaded rod 9 installed therein.

 The threaded rod 9 is in engagement with the threaded sleeve 6 and with the pins 8 of the guide sleeve 7. To engage the threaded rod 9 with the pins 8 on the side surface of the threaded rod 9 there are screw grommets 10, which, for the convenience of assembly in the tail of the rod 9, smoothly transition into longitudinal grooves.

 The mold works as follows.

 When the mold is opened, the ejector unit (plates 4 and 5) moves in the longitudinal direction relative to the threaded rod 9. In this case, the guide sleeve 7 with the pins 8 moves in the longitudinal direction. The pins 8, which are meshed with the screw grooves 10 of the threaded rod 9, cause the latter to rotate, causing it to turn out of the casting along the threaded sleeve 6 with a step corresponding to the threaded step of the casting.

 Thus, the translational motion of the ejection unit is converted into rotational motion of the threaded rod.

 When closing the mold, the work is carried out in the reverse order.

 The advantages of the proposed technical solution are that in the absence of rods of a segment section, the reliability of the mold increases; when combining the copy pair and the forming profile, the accuracy of the product profile increases; due to the absence of interrupted thread, the product’s power characteristics are improved, and the possibility of obtaining through thread and thread in a “blind” product indicates the expansion of the technological capabilities of the mold

Claims (1)

 A casting mold for investment casting with internal threading, comprising a movable die, a fixed die, an intermediate plate, an ejection block, a threaded rod meshed with a threaded sleeve fixed from rotation, and a pin meshed with a screw groove, made on the lateral surface of the threaded rod, characterized in that it is provided with a guide sleeve located in the ejection unit, and an additional pin that engages with an additional screw groove, in performed on the lateral surface of the threaded rod, while the threaded rod is installed in the guide sleeve, the pins are rigidly fixed to the lateral surface of the guide sleeve, and the threaded sleeve is fixed in a fixed matrix and secured against rotation by the intermediate plate.