SU692699A1 - Apparatus for centering and clamping a workpiece - Google Patents

Description

The invention relates to a machine tool industry and can be used to fasten parts on machine tools.

Devices of a similar purpose are known with four cams being moved towards each other, each pair arranged in pairs in two planes of symmetry of the blank 1.

The disadvantage of the proposed device is the asynchronous movement of the cams, adversely affecting the accuracy of the centering of the workpiece.

The purpose of the invention is to improve the accuracy of centering.

For this, each pair of cams, at least one of which is made in the form of a prism, is installed with the possibility of joint movement of both cams in one direction in one of the planes of symmetry of the workpiece.

In addition, in the housing of the device there are movable sliders in the planes of symmetry, carrying each specified pair of cams, one of which is fixed to the slide and the other is made movable from

drive installed on the same. slide.

Another modification of the device is that a pair of cams moved in one plane of symmetry of the workpiece is made with prismatic clamping surfaces, and a cylindrical surface is formed on the outer surfaces of both cams, coinciding with or parallel to the nominal axis of the workpiece, and the second a pair of cams is provided with prismatic clamping surfaces that are in contact with the specified cylindrical surface.

In addition, one pair of cams. spring-loaded in the direction of the workpiece surface and provided with pins, and the other pair of cams is equipped with a.

0 cloned planes in contact with the indicated pins.

FIG. 1 shows the described device with power cylinders; on 5 fng. 2 and 3 - section A-A and B-B in FIG. one; in fig. 4 .- section BB in FIG. 2; in fig. 5 and 6 a section of GG and DD in FIG. I, FIG. 7 - device with two-digit screw; in fig. 8-10, cuts of EE, MF, and AND in FIG. 7s in FIG. 11 is a view along arrow K in FIG. 7 / --------- g: ,, - .. ...-.-, .. -, the body 1 of the device is formed by guides 2 and 3 of linear motion, closed by slats 4 (Fig. 1- 6). Slides 5 and 6 .. are placed in guides 2. They carry a pair of cams 7 and 8, and the cam 7, made in the form of a prism, is fixed on the slider 5, and the flat cam 8 is fixed on the rod 9 of the piston of the power cylinder 10, the case of which is fixed on yilzune b. The sliders 5 and b, rigidly connected by the rod 11, form one common slide, spring-loaded with spring 12, the force of which is chosen so that it can only overcome friction in the guides. In the guides 13, the sliders 14 and 15, which also form a common slide, as they are rigidly connected by a rod 16. The slide is spring-loaded with a spring 17, which is selectable. Similarly to the spring 12. The slide carries a cam 18 fixed on it, and the body of the power cylinder 19, on which 20 is mounted a flat cam 21. Before loading the bottom-up pressure. connected to the rod end of the chain: ditch 10 and 19, cams 8 and 21 from led to the cylinder bodies. At the same time, the sliders 5-6 and 14-15 with the springs .12 and 17 are retracted towards the sliders 5 and 14, with the result that the cams 7 and 18 are as far as possible from the centering axis. ; a) The pressed workpiece is installed in one prismatic cam 7 and then pressure is connected to the piston cavity of the cylinder 10. The rod 9 is moved to the right, by the cam 8 behind the pressing workpiece. At the same time, the X-X symmetry plane is captured: the shutter is clamped, then the pressure is connected to the first cavity of the cylinder 19. The rod 20 is moved forward until it touches the bag 21 with the surface of the workpiece. After this, the cylinder body 19 begins to peremadatsya in the opposite direction relative to the porin, prior to the force of the spring 17 and moving the common slider 14-15 until the cam 18 of the cam 18 is loaded with the surface of the catch. If, in this case, the plane of symmetry of the U-U of the workpiece does not coincide with the prism of the cam 18, then this tool, by means of the workpiece clamped in cams 7 and 8, moves them along with the slider 5-6 along the guides 2 thereby catching the plane U-U symmetry. In this position, the clamping is clamped by cam claws 18 and 21. Another embodiment of the device is shown in FIGS. 7-11. , In the housing 1, mutually perpendicular guides 2 and 3 are made. The coils 2 are formed directly by a projection on the body part having the shape of a dovetail, the guides 3 are formed by patch slats 22 and 23 of the same cross section. On the guides 3, the slides are made at the same time as the cams 24 and 25 in the form of prisms and are spring-loaded in the direction of the axis of the workpiece with weak springs 26 abutting on the stationary supports 27. The cams have sections 28 and 29 of a cylindrical surface parallel to the nominal axis. axes of the workpiece. Each cam carries a cylindrical pin 30, the gaps in the guides are selected by wedges 31. On the guides 2 there are slides 32. and 33, bearing nuts 34, which interact with the left and right cuts of the double-digit screw 35. The last It is located in the housing 1 between the compression springs 36. The gaps in the guide sliders are chosen by wedges 37. The cams 38 and 39, also made in the form of prisms, are fixed on the sliders. On the outer surface of the cam 39, inclined planes 40 are fabricated. Before loading the workpiece, cams 38 and 39, at, are screwed with screw 35. In this inclined plane 40, acting on the pins 30, the cams 24 and 25 are set apart. Having loaded the workpiece into the device, the cams 38 move the screw 35 and. 39 towards each other. As a result of this, the planes 40 do not prevent the cams 24 and 25 from coming together, which, under the influence of the springs 26, come into contact with the surface of the workpiece and catch the plane of its symmetry. The working planes of the prisms of the cams 38 and 39 approach the areas 28 and 29 of the cams 24 and 25 and are in contact with them. If one of the sections 28 or 29 contacts the prisms of the cams 38 and 39, then under the influence of the contacting prisms the cams 24 and 25 move to the left or the right together with the workpiece, thereby making the plane of symmetry of the workpiece, And in this position they are clamped by the cams 38 and 39 If only one of the cams 38 and 39 is in contact with areas 28 and 29, then both cams, together with the sliders and the screw 35, are shifted up or down, —jump. will be clamped by both cams 38 and 39.

The type of drive is selected regardless of the features of the copy options. Thus, in the first variant, means for manually moving the cams, for example screws, can be used, while in the second variant, means for mechanizing operations, for example, power cylinders, are easily used. In addition, in the second embodiment, you can use a design with a slider, HecyuuiM cam and drive. If the planes of symmetry of the workpiece intersect at an angle other than straight, then in the case 1, the guides are arranged, arranged accordingly. In this case, both cams, moving in one plane of symmetry, can be made in the form of prisms and in the first embodiment. In the same place, sliders 5-6 and 14-15 can be made practical without rods 11 and 16.

By using the proposed devices for centering and clamping blanks, the dimensions of which are within relatively narrow limits, it is possible to do without springs 12, 17 and 36, making it convenient to operate the device by appropriately limiting the movements of the sliders in the first version and the screw in the second version.

A further increase in centering accuracy is achieved by creating backlash-free guides, for example, by clamping the cams on the guides after centering.

By the known means, it is possible to change the constructions described above in order to center the blanks passing through the device.

From the options described it can be seen that the proposed device provides the centering of the workpiece with cams in two planes of its symmetry, regardless of the synchronism of cam movement, and allows to increase the accuracy of the centering of the heats while reducing the accuracy requirements for the manufacture of centering devices.

As can be seen from the first option, the same feature allows using extremely simple means with the simplest kinematics to mechanize the process of precise centering and clamping of the workpieces, thus ensuring an increase in labor productivity and a reduction in labor intensity.

5 Formula and inventions

1. A device for centering and clamping a workpiece with four cam-moving jaws JQ, arranged in pairs in two planes of symmetry of the workpiece, differing from the fact that, in order to increase the accuracy of the centering, each pair of jaws: made in the form of a prism, installed with the possibility of joint movement of both cams in one direction in one of the planes of symmetry of the workpiece. 2. The device according to claim 1, characterized in that in the case of the device there are slides movable in planes of symmetry carrying each indicated pair of cams, one of which is fixed 25 to the slider and the other is movable from the actuator mounted on the same slider.

3. The device according to claim 1, characterized in that the pair of cam pieces, moved in one plane of symmetry of the workpiece, are made with prismatic clamping surfaces, and a cylindrical surface with an axis coinciding with or parallel to the nominal axis of the workpiece is formed on the outer surface of both cams, moreover, the second pair of cams is provided with prismatic clamping surfaces in contact with said cylindrical surface.

4. The device according to p. 1, is different from the fact that one pair of cams is spring-loaded towards the surface of the workpiece and is equipped with

5 pins and a friend a couple of cams

provided with inclined planes, in contact with the indicated pins.

Sources of information taken into account in the examination

50 1. Belousov A.P. Design, machine tools, Higher School, 1964, p. 154, p. U1 13.

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