SU55497A1 - Precision groove milling machine with precise spacing between them - Google Patents

Description

The machine is designed for cutting through the cutters of particularly narrow slots having a width of 0.1 mm and apart from each other over a distance that can vary by no more than + 0.005 mm.

Quite often in parts of knitted machines there are slots that serve as boxes, in which the loop-forming plates, so-called platinum and needles, move.

Thus, the machine is specially designed for machining parts in hall (knitted) machines, the machine can, however, find application in all cases when it seems necessary to cut grooves located on a plane parallel to each other and characterized by the size and accuracy specified higher. For this, according to the invention, in the proposed machine using a correction bar, the correction device is coupled with the nut of the table spindle to use a fixed dividing disk for moving the table. At the same time, for sampling the dead stroke of the table, the spindle screw of the latter consists of two parts, tied by a spring located in the tide of the table on the second nut, which may

displace axially relative to the table.

To transmit the rotation of the spindle in the machine, helical gears are used to use small diameter cutters.

Elastic, for example, rubber gaskets are enclosed under the base of the engine mounted on the moving part of the bed to eliminate the transmission of vibrations to the cutting tool.

In FIG. 1 is a side view of a precision machine; FIG. 2 shows a CD in FIG. 3, FIG. 3 is a section along the line AB in FIG. 2. S

The main parts of the machine are: a bed with a slide and a feed mechanism, a milling head and a traverse with a table equipped with a dividing mechanism and a device for sampling dead strokes.

The bed / machine has guides in which the slider 2 moves. The movement of the slider is not reported by the feed mechanism (shown in the drawing), which is either a well-known actuator slide, or a device with a reversing screw, or, finally, a hydraulic device.

The slider 2 carries at the end of the milling head 4.

In addition to the horizontal guides for the slider 2, the frame 1 also has vertical guides along which the traverse 6 moves.

The milling head 4 is a crankcase within which a spindle speed change mechanism is enclosed. The latter is made in the form of a multistage gearbox and informs the rotation of the spindle with the speed corresponding to the required cutting mode.

The movement transformed by the gearbox is borrowed from the electric motor 5, located on the head and separated from the last elastic gasket, by absorbing the vibration of the electric motor.

In its lower part, the head has two protrusions, one of which has bearings. In the latter, the spindle 6 rotates, ending at the center (Fig. 2). The opposite protrusion of the head carries the second fixed center 7.

A mandrel 8 is installed between the movable center and the center of the spindle, which is connected with the spindle flange with a finger and rotates together with the latter. A milling cutter is clamped to the mandrel using a nut and spacer rings. The location of these organs is such that the plane of the cutter coincides with the direction of movement of the slider.

Spindle 6 is reported to rotate by means of a pair of gears, one of which is located on the spindle, and the second on the vertical roller connected to the gearbox. Such a device allows the spindle and its drive to be made in very small sizes, allowing, therefore, the use of cutters also of small diameter, starting from 25 mm.

The latter circumstance is one of the distinguishing features of the machine, very significant, since the beating of the cutters with such a diameter is insignificant; The manufacture of such cutters with a thickness of 0.1 mm is incomparably simpler than cutters of a larger diameter.

The slight beating of the cutters already noted is a significant factor in the successful cutting of the grooves, as well as their relatively easy manufacture determines the economic side of things.

Traverse 3 is a rigid shape that can move along the vertical bed guides in order to set the depth of the groove to be milled. A screw 10 (Fig. 2) is used to move the crosshead, which is included in the nut of the column // attached to the base of the bed. The screw is informed by the rotation of the flywheel 12 (Fig. 1) through the screw and the worm gear / 5. The raised traverse is secured by clamping knobs 14.

On the upper horizontal surface of the traverse, there are guides arranged perpendicularly to the slider guides and serving them for guiding the table 15 sliding in them. The table is intended for mounting a product or jig on it; for this purpose, the table is provided with L-shaped grooves.

Moving the table by a distance equal to the pitch of the grooves is achieved by turning the separating screw 16 (Fig. 2), which carries a separating handle 17 at its end, the pin of which can be inserted into one of the holes of the separating disk 18 (Fig. 1, 2). The latter is fixed on the head bearing 19, mounted on the traverse and bearing the axle of the separating screw.

In order to increase the accuracy of the described separating device and eliminate the influence of the errors of the separating screw, a correction mechanism is introduced into the device, which is as follows. The separating screw nut 20 ((FIG. 2) has the ability to rotate inside the yoke 21 attached to the end of the table and resting on the nut flange. A crown 22 is mounted on the nut (Fig. 3, having an extension on which the stop 28 acts pressure of the spring 24. The stop tends to turn the nut clockwise. The right end of the lever 25, which revolves around an axis fixed in the cage, impedes this. At the left end of the lever 25 a roller 26 is installed, which can roll when the table moves along the surface of the corrective ruler 27 attached to traverse e.

The working surface of the correction ruler is curvilinear and has a certain height in each cross section, depending on the magnitude of the error of the dividing screw in this place.

The operation of the described mechanism is such that the movement of the table is the result of the joint action of the separating screw and the correction ruler on it. The magnitude of this movement is determined by the angle of rotation of the screw, depending on the number of holes of the separating disk, and the angle of additional rotation of the nut, which is performed automatically and depends on the height of the corrective ruler in a given cross section.

The algebraic summation of these two displacements can ensure the movement of the table with an accuracy that lies beyond the requirements imposed on the grooves and is determined only by the carefulness of the manufacture of the mechanism and the relative dimensions of its parts.

Being similar in their idea to similar devices used for the same purpose in precision marking and drilling machines “CIP, the mechanism shown in the drawing has a fundamental difference from them, namely that these devices act on the nonius of the machine without communicating directly to the table . The described mechanism, acting on the nut of the dividing screw, reports the additional movement directly to the machine table.

In addition to the correction mechanism, the dead-stroke sampling mechanism was introduced into the separating device, eliminating the influence of the latter on the accuracy of the division. This mechanism is as follows. The separating screw 16 ends with a trunnion provided with a prismatic key and entering into a sleeve 28 (FIG. 2), rotating together with a screw in the middle sub-carrier 29 mounted on the yoke 3. The same sleeve also includes a pin of auxiliary screw 30 having a prismatic key, having same thread pitch as dividing screw. Rotating with the divider screw, the auxiliary screw 30 retains the possibility of axial movement, since the prismatic pins do not prevent the latter. The second end of the auxiliary screw is located in the bearing 31, resting against the last bead. On the auxiliary screw is put on the nut 32, which has a flattened collar.

The table is equipped with a tide, bored out concentrically to the auxiliary screw.

The collar of the nut 32 enters the tidal bore freely, but the nut is prevented from rotating by a locking screw 55 screwed into the table body so that the entrance to the slot of the nut collar leaves the nut axially displaceable.

Between the collar of the nut and the bottom of the tide there is a strong spring 34, which is compressed so that it can overcome both the inertia of the table and the resistance of the friction forces.

The degree of compression of the spring remains unchanged and, consequently, the pressure exerted by the spring on the table is constant and independent of the position of the table, since the equality of the steps of the separating and auxiliary screws ensures the equality of the paths passed by the table and the nut 32, which is the support spring 34. At the same time, the pressure developed by the spring provides a sample of all possible gaps in the joints of the separating mechanism, because under the pressure of the spring the table is pressed against the collar of the nut 20 through the yoke 21. Lastly, through the turns of the thread pressed unilaterally to the thread of the separating screw 16,

Forcing, in turn, the flange of the screw to press against the bearing 19 fixed on the traverse.

Due to the constant in direction and sufficient force, the possibility of gaps in the joints of the separating mechanism and the influence of dead strokes on the accuracy of the latter are eliminated.

The subject matter of the invention.

Claims (4)

1. A precision machine for milling grooves with a precise pitch between them using a correction bar, characterized in that the correction device is coupled with the nut of the table spindle to be used for Relapsing the table of a fixed separating disc. 2. The form of the machine according to claim 1, characterized in that, in order to sample the backlash of the table, the spindle of the latter consists of two parts, bulged by a spring located in the tide of the table on the second nut, which can shift in the axial direction relative to the table . 3. In the machine on the PP. 1 and 2 are used to transmit the rotation of the spindle of helical gears, in order to use cutters of small diameter. 4. In the machine on the PP. 1-3, use elastic rubber pads under the base of the engine mounted on the moving part of the machine in order to eliminate the transmission of vibrations to the cutting tool.