SU1764969A1 - Mandrel for making holes in the parts - Google Patents

Abstract

Use: manufacture of parts accurate plastic deformation. Summary of the invention: the device comprises a mandrel 1 with a drive and a table 4 with an auxiliary ring 5 mounted on it. The increase in labor productivity is achieved by the fact that the auxiliary ring is made in the form of an annular holder 6 rigidly fixed on the table and at least three ring sectors placed inside sleeves, clamped by an annular spring 8 installed in the groove 9 on the outer surface of the sectors, and mated with an annular yoke along a conical surface, the top of which is directed to the table, while the annular The boom is equipped with a stop 10 fixed on the opposite end of the cage with an axial clearance relative to the ring sectors, the value of which corresponds to the expression: a Od Do / 2tg “, where a is the axial clearance, mm; Od - diameter of the gauge part of the mandrel, mm; D0 is the diameter of the hole formed by the inner surfaces of the ring sectors, m; a - half of the angle of the cone of the mating surfaces of the ring cage and ring sectors, hail. The laboriousness of the flooring operation is reduced by eliminating the need to install and remove the auxiliary ring during the refining of each part. 3 and / ;. .: (L with VI ON 4 Yu Os Yu Yu Out I

Description

The invention relates to the technology for the manufacture of parts by precise plastic deformation, in particular, to devices for backing holes in parts.

A device for mandrel opening in parts is known, comprising a motorized mandrel and a table on which the workpiece is mounted.

The disadvantage of this device is low labor productivity in the manufacture of parts, since it does not contain mechanisms or devices to eliminate or prevent distortion of the end portions of the part hole as a result of the edge effect. Elimination of the effects of the edge effect on other technological equipment, performed by a separate operation, leads to an increase in the labor intensity of manufacturing parts.

It is also known a device for machining holes in parts, including a mandrel with a drive for mandrel holes and a lathe, which serves to trim the ends of the part after trimming in order to remove the hole sections distorted by the edge effect.

The disadvantage of this device is low productivity in the machining of holes, since in order to obtain accurate along the entire length of the hole, trimming of the ends on a lathe is performed by a separate operation that is not aligned in time with the hole of the hole. Therefore, the overall processing time of the part is long.

Closest to the proposed device, by its technical essence, is a device for arching holes in parts, containing a motorized mandrel and a table with a one-piece auxiliary ring mounted on it. The ring is made of a material, the elastic properties of which are higher than the elastic properties of the material of the workpiece, and forms a single machining surface with the hole being machined,

A disadvantage of this device is also low labor productivity in mandrel drilling. This is due to the fact that after each detail has been added, the auxiliary ring is removed from the device table to raise the mandrel to its original position. The need to remove the ring is due to the fact that during the reverse movement of the mandrel (up, to its original position), the latter will deform the auxiliary ring attached to the table, which will lead to rapid wear or breakage of both the ring and the mandrel. The need to remove the one-piece auxiliary ring after the dorne of each part and install it on the table before each new part is processed significantly increases the piecework time of the operation, which results in low productivity of work on the addition of parts.

The aim of the invention is to increase labor productivity in case of flushing.

This is achieved by the fact that the auxiliary ring is made in the form of an annular cage rigidly fixed on the table, and at least three annular sectors placed inside the cage, pressed by an annular spring mounted in the groove on the outer surface of the sectors, and conjugated with the annular cage along the conical the surface, the top of which is directed towards the table, while the annular cage is equipped with a stop rigidly fixed on the opposite end of the cage end with an axial clearance relative to the annular sectors, the size of which corresponds to There is the following expression:

Od-in

OK

2 tg "

(D

where a is the axial clearance, mm;

Od-diameter calibrating part of the mandrel, mm;

Ook is the diameter of the hole formed by the inner surfaces of the ring sectors, mm;

and - half of the angle of the cone of the mating surfaces of the ring cage and ring sectors, deg.

FIG. 1 shows the device, a general view; in fig. 2 - ring sectors and ring holder, plan; in fig. 3 - a remote enlarged view of conjugation of annular sectors with an annular cage and an emphasis.

The device (Fig. 1, 2) contains a mandrel 1, having a calibrating part with a diameter Od, which is connected by a rod 2 with a drive, for example a hydraulic one. On the back of the mandrel there is a conical section 3. On the table 4 of the device, there is an auxiliary ring 5, made in the form of an annular cage 6 rigidly fixed on the table 4, and annular sectors 7 (in this case, three) placed inside the cage 6.

Ring holder 6 and sectors 7 are made of a material having elastic properties that are higher than the elastic properties of the material of the workpiece, for example, from steel 65 GOST 1050-88. Sectors 7 preloaded annular spring 8 installed in the groove 9 on their outer surface. An annular stop 10 is attached to the free end of the holder 6.

The interface between the ring sectors 7 and the holder 6 is made along the conical surface 11, with its top 0 directed along the working movement of the mandrel 1, and the ring stop 10 forms an axial gap 4 with the sectors 7. At 12 in FIG. 1 designates the product to be processed - the steel frame of an explosion-proof electric motor (material - Art. ZPS GOST 380-88).

The device also contains a mechanism (for example, hydraulic) axial clamping of the part. Letters 00k and d in FIG. 1 and 3 denote, respectively, the diameter of the hole formed by the inner surfaces of the annular sectors prior to construction (DOK O0.d., where Оo.d is the diameter of the workpiece hole to be preformed, mm) and half the angle of the cone 11 of the matching surfaces of the yoke 6 and sectors 7.

From FIG. 3 it can be seen that when sectors 7 are moved apart, when the mandrel is raised to its initial position, point E of the sector will move to point B, having made a radial movement | BC.

Expression (1) is derived from the BCE triangle (Fig. 3, based on the condition of increasing the diameter of the hole formed by the inner surfaces of the sectors, from the size of this diameter to the height to a value equal to or greater than the diameter of the mandrel when it rises to its original position, i.e. .

In C

Dn-DC

From the triangle ALL:

 CE

tg a

(3)

Substituting (2) in (3), receive the expression (1). The angle a is set to a larger minimum limit angle, ensuring no jamming (for given conditions a 12 °), but less than 90 °. For example, 20 ° are accepted. For a specific example of the bedding of an electric motor base H 180 Od 327.045 mm, O0.k. O0.d. 323.6 mm. Substituting the original data into expression (1), we get: a 4.73 mm. Take, for example, a 5 mm.

The device works as follows. In the initial position, the ring spring

The gum 8 (Fig. 1) compresses the ring sectors 7, which with their outer conical surfaces 11 are centered on the conical surface of the ring cage 6. When

In this, the diameter 00k of the hole formed by the inner surfaces of the sectors 7 is equal to the diameter O0.d. holes of the workpiece. Dorn is in the highest position.

10 The workpiece 12 is mounted on the annular sectors 7 of the auxiliary ring 5 and is pressed against them with an axial force generated by the clamping mechanism (not shown in FIG. 1-3). Then mandrel 1

15 is lowered, flaking of the opening of the product 12. Throughout the entire filling process, the sectors 7 are axially pressed by the pressing mechanism and the axial force of the mandrel is pressed against the surface of the table 4 as well as the conical surface 11 of the yoke 6. givania sectors 7 on the conical surface 11 of the holder 6 in the direction of the top 0 of this

25 surfaces, as a result of which the sectors are tightly compressed among themselves, and the diameter of the DOK hole formed by their internal surfaces is fixed at 00d. At the same time, the hole formed by the inner surfaces of the sectors 7, with the hole being machined, constitutes a single machining surface.

After passing through the auxiliary ring 5, the mandrel 1 is lowered into the cavity of the table 4. The mandrel drive is disconnected, the mandrel is disconnected from the actuator stem 2, the stem is lifted to the extreme upper position, the machined product 12 is removed from the desk 4. Then the actuator stem 2 is lowered into the edge 40 the lower position, connect it with the bore and lift the latter to the extreme upper position. During the upward movement of the mandrel, with its conical surface 3 enters the hole formed by the inner surfaces of the sectors 7. As a result, the axial and radial The pressure of the mandrel on the inner surface of the sectors 7 is moved along the conical surface 11 of the holder 6.

50 At the same time, point E of the sector (Fig. 3) moves to point B, i.e. The axial displacement of sector 7 is equal to the value of a, determined by expression (1), and the radial displacement - to the value of the sun, defined by expression (2). So

55, the diameter of the hole formed by the inner surfaces of the sectors increases from DOK 00d to a value not smaller than Od, the calibrating part of the mandrel, whereby the mandrel freely passes through the auxiliary ring 5. After the mandrel passes through the ring 5, its sectors 7 under the action the springs 8 are compressed in the radial direction and the diameter of the hole formed by the inner surfaces of the sectors again becomes equal to 00 K O0d. In this case, the sectors 7 under the action of their own weight fall down by the amount of displacement a, with their conical surfaces centered on the conical surface 11 of the ring cage 6. When the road 1 reaches the extreme position, its drive is turned off, the cycle is completed.

Thus, the device makes it possible to significantly increase labor productivity in the installation of the hole in the parts by eliminating the need to remove the auxiliary ring from the table of the device after the filling of each part and installing this ring on the table before each part.

Claims (1)

Claims device for arching holes in parts, containing a mandrel with a drive and a table with an auxiliary ring mounted on it, characterized in that, in order to increase labor productivity in the development of burnishing, 7 the ring is made in the form of an annular cage rigidly fixed on the table and at least three annular sectors placed inside the cage preloaded an annular spring mounted in the groove on the outer surface of the sectors, and the conjugate and annular yoke along a conical surface, the top of which is directed towards the table, while the annular the cage is equipped with a stop rigidly fixed on the opposite end of the cage end with an axial clearance relative to the ring sectors, the value of which corresponds to the following expression: but Rd DO.K 2 tga where a is the axial clearance, mm; Od-diameter calibrating part of the mandrel, mm; DOK — diameter of the hole formed by the inner surfaces of the annular sectors, mm; a - half of the angle of the cone of the mating surfaces of the ring cage and ring sectors, hail. Riga.g I 9V d