WO2015102515A1

WO2015102515A1 - Method for machining an asymmetrical workpiece in a single setting and device for fastening a workpiece

Info

Publication number: WO2015102515A1
Application number: PCT/RU2013/001209
Authority: WO
Inventors: Андрей Александрович СЕВАСТЬЯНОВ; Алексей Михайлович ЩИЛОВ
Original assignee: Андрей Александрович СЕВАСТЬЯНОВ; Алексей Михайлович ЩИЛОВ
Priority date: 2013-12-31
Filing date: 2013-12-31
Publication date: 2015-07-09
Also published as: RU2600685C1

Abstract

The present invention is intended for the machining of asymmetrical workpieces having profiled surfaces, and is a device for fastening an asymmetrical workpiece (16) in the position of its initial setting relative to the axis (3) of the centres of a machine tool in which, with the aid of clamping devices (4a, 4c), the workpiece is fastened in a plurality of cross sections near a region to be machined (22) such that the workpiece can be rotated about the axis (3) of the centres (15) of the machine tool, thus ensuring the stability of the workpiece and the accuracy of the setting when the workpiece interacts with cutting instruments having differently directed cutting forces in different regions to be machined (22). The device is adapted to be housed in a CNC machine tool for carrying out the above method for machining workpieces in a single setting without the need for manual labour and with improved machine tool productivity.

Description

Asymmetric machining method

blanks from one installation, machine and device for securing blanks

Technical field

The invention relates to machine tool equipment for the machining of workpieces of asymmetric products having shaped surfaces, namely, to methods for performing the complete finishing machining of multidisciplinary workpieces from various materials, including the complete removal of technological allowances, with the least amount of auxiliary operations for installing and removing the workpiece with performing various operations in the cycle of machining an asymmetric product blank, in particular, to methods for processing blanks vki from one installation and devices for their implementation.

State of the art

It is known that the technological processes of processing workpieces for the manufacture of multidisciplinary products consist of technological (working) operations, which, in turn, are composed of technological transitions, which are accompanied by a change in the state of the workpiece and are performed with the same means of technological equipment, and auxiliary transitions, representing a complete part of a technological operation consisting of human actions and (or) equipment that are not accompanied by a change in state preparations, but necessary to complete the technological transition.

It is also known that the main parameters characterizing the technological process of manufacturing a product of a given size and shape from a workpiece are the parameters due to the technical characteristics of the machine equipment: allowable dimensions of the processed material; number and sizes of cutting tools; rotational speed of the working shaft, which determines the cutting speed; method and feed rate, characterizing the speed of processing parts; engine power, as well as parameters due to the equipment of the machine with the necessary additional equipment, providing increased productivity of the machine, as measured by the number of products manufactured per unit time. At the same time, an important part characterizing the efficiency of the technological process and the productivity of the machine is the part of the technological operation, known as the “installation”, performed at a constant position of the workpiece on the machine. The methods of fixing the workpiece in the machine are determined by the design features of the machine, the shape and size of the workpiece, the ability to perform one or more necessary technological operations from one installation of the workpiece in the machine to reduce processing time. It is clear that the more installations in the process, the lower the accuracy of positioning, the greater the time spent on auxiliary transitions and lower labor productivity.

When setting the task of reducing the time spent on auxiliary transitions, the greatest attention is paid to the use of various devices in the processing machines that allow performing the largest number of technological operations at one installation of the workpiece, while ensuring the specified processing accuracy by fixing or supporting the workpiece in a certain position.

It is known that during machining in order to obtain the required surface, for example, turning, milling, drilling, grinding, it is necessary to inform the tool and the workpiece of movement consistent with each other. These movements in the machines are divided into main movements, called cutting movements, and auxiliary movements, called feed movements. Auxiliary movements are necessary for preparing the cutting process, and they include: movements associated with setting up and setting up the machine, its control, securing and releasing the part and tool by bringing the tool to the machined surfaces and its retraction; movements of devices for automatic size control and other movements. Auxiliary movements can be performed automatically and manually. So, for example, in turning machines, the main movement (rotational) is made by the workpiece, and the feed movement (translational) is made by the cutting tool, in milling machines the main movement (rotational) is made by the cutter, and the workpiece (linear or curved) can perform the workpiece. CNC multi-purpose machines for machining parts, such as turning, drilling, milling and boring machining centers, can perform machining with a rotating tool, have the ability to accurately angularly position the spindle and rotate the spindle in the circular feed mode, and also contain devices for fixing the workpiece as in a stationary position , and with the possibility of rotation. Therefore, all types of turning can be performed on these machines, as well as milling, drilling, boring and other operations (machining of off-center holes, milling of flats, keyways, shaped grooves, longitudinal and transverse planes, profile grooves and other elements).

It is known that with all the variety of designs of machine tools for machining, they all consist of the main parts: a bed, a working table (or front and rear headstock) with devices for securing the workpiece (for example, chucks, faceplates, collets, centers, clamps, lunches, mandrels ), the working shaft (or spindle) for attaching cutting tools (saws, mills, knives, drills) and giving them rotational movement, caliper, drive mechanism, and contain additional devices for feeding material, guides and clamping stroystva. To be able to change the position of the working shaft or spindle, they are mounted on a support moving along the guides. The drive mechanism serves to communicate movement from the electric motor to the cutting or feed parts of the machine. Guides and clamping devices are used for the correct orientation of the workpieces relative to the cutting tool and fixing them in the corresponding position during positional processing of the workpiece to the specified size and shape in each operation. At the same time, special devices are used to fix the workpiece in the desired position, which should be located as close as possible to the workpiece processing zone.

It is known to fix the workpiece by clamping the workpiece with the ends between the centers of the machine placed rotatably on the work table, and various technical solutions are known for devices for supporting the workpieces in the machine during their machining, for example:

1) devices to support long symmetrical products, which are bodies of revolution, bottom and side when they are installed in the centers the machine (SU, 1662799, Al; RU, 2199427, C2), for example, various lunettes mounted on the machine bed with the ability to move in the longitudinal direction along the guides of the bed (RU, 2006134171, A);

2) devices for fixing an asymmetric workpiece in the centers of processing machines (for example, ES, 2339316, B1), for fixing an asymmetric workpiece with the possibility of its rotation around the axis of the centers of the machine (AT, 385454, B);

3) devices for fixing thin-walled blanks having internal cavities in a certain position on the machine by compressing their surface with elastic elements under the action of certain forces of hydraulic elements (US, 6182977, B 1).

4) self-centering lunettes used in lathes to support long axisymmetric billets and mounted on transverse calipers in the zones of formation of nodes of vibration heights of the processed long workpiece and equipped with double spherical clamping rotating rollers, the rotation plane of which passes in a plane passing through the longitudinal axis of the workpiece, and step drives (RU, 2494840, C1), for example, mounted on the cross support of the machine to control the level of vibration and by changing the pressure in the servo drive of the rest, counteracting the pressing force on the working roller of the rest (RU, 99113293, A).

However, the above devices only ensure that the workpiece is in a certain position during its processing, but does not reduce the number of auxiliary transitions and the number of installations in technological operations.

Known CNC lathe (RU, 71920, U1), containing a bed, headstock, tailstock, carriage, apron, slide, tool holder and at least one lunette to support long shaft blanks, installed on the side opposite to the tool holder, on the same longitudinal guides of the bed on which the tailstock is mounted. The number of lunettes depends on the length of the processed shaft. Each lunette contains two swivel legs, covering the work shaft from two sides, and a sliding support, axis which is located in the plane of symmetry of the rotary tabs with each other. At the ends of the legs and the retractable support are fixed rollers interacting with the outer surface of the work shaft. Each lunette contains a drive for turning the legs and extending the supports and the lunettes are installed so that the plane of symmetry of the rotary tabs is located at an angle of 70 ° ... 85 ° to the vertical plane passing through the axis of the machine centers. The headstock is mounted on the bed and contains a hollow spindle, a spindle rotation drive and two chucks fixed at the ends of the spindle: one on the right and left end of the spindle. The tailstock is mounted to move along the longitudinal guides located on the upper plane of the bed.

The machine operates as follows. Along the length of the bed on its longitudinal guides located on the upper plane of the bed, lunettes are installed, the rotary tabs of which are spread apart. The shaft to be processed is clamped in the headstock chuck and pressed with the tailstock's pinole, the shaft is fixed in the lunettes, closing the swivel legs and extending the retractable bearings. Then the shaft is machined: in accordance with the commands from the CNC system, the rotation of the spindle headstock with the machined shaft and the movement of the carriage with an apron in the longitudinal direction and the slide with the tool holder in the transverse direction are controlled. The processing process is carried out continuously along the entire length of the shaft. In order to process the shaft end, the shaft is reinstalled by inserting the shaft into the hollow spindle and clamped approximately in the middle of its length in both spindle head cartridges without the participation of the tailstock. Then again fix the shaft with lunettes and process the ends of the shaft.

However, the lathe described above (RU, 71920, U1) is suitable for turning only long workpieces in the form of axisymmetric bodies of revolution, for example shafts, from at least three installations: installing the shaft in centers and lunettes for turning the shaft in length and subsequent shaft recess; installing the shaft with one for the most part in the headstock with the protrusion of the smaller part from the headstock for subsequent trimming of one free end and changing the position of the shaft with installing the shaft with its other most for the headstock with the protrusion of another smaller part of the headstock for subsequent trimming of the other free end . In addition, each of the installations b requires a significant investment of time, which reduces the productivity of the machine. At the same time, the described lunettes provide only the fixation of the position of the rotating outer surface of the workpiece relative to the axis of the centers of the machine and then the projection of the protruding shaft end relative to the axis of the centers of the machine by supporting the workpiece on the rollers of the lunettes, but do not exclude the reinstallation of the workpiece during its processing.

Known machines for the profile processing of rotating and stationary asymmetric bodies of revolution with shaped surfaces, for example, screw, for the manufacture, in particular, of the legs of chairs, tables, stair balusters.

For example, the CENTAURO Star-Star turning and milling machine (Italy) is known, which contains a rotating rest for supporting and centering the workpiece, with an additional cutter for rounding the workpieces, while the workpiece is installed in the machine centers with preformed coaxial technological protrusions at the ends of the workpiece.

Known turning and milling machine with CNC Galaxy SH 1800 CNC-S (China) with the ability to simultaneously work with three cutters, containing a lunette for rigid fixation of the processing zone. The machine allows the tool of the 1st caliper to grind the workpiece under the diameter of the rest, using two controlled copy cutters to produce rough and finish cuts, which allows you to profile the part in one pass of the machining group. In this case, the workpiece is installed in the centers of the machine pre-formed at the ends of the coaxial technological protrusions with recesses.

Known CNC turning and milling machine "INT () REX SK1-1500" (Spain), which allows sharpening bodies of revolution without using a mechanical copying unit or templates, containing a horizontal milling unit with CNC for milling notches, spirals and other shaped surfaces and a pneumatic rest with three adjustable rollers and adjustable clamps to support the workpiece while grooving and cutting helical grooves. To rotate long and narrow workpieces, the machine can be equipped with a pneumatic clamp with three adjustable rollers mounted on one of the heads, and contain two CNC copy machines and a hydraulic device for processing the workpiece with a diameter equal to the diameter of the lunette. In this case, the workpiece installed in the centers of the machine pre-formed at the ends of the coaxial technological recesses.

However, the use of the above-mentioned lunettes and clamps in the above-described machines only provides support and centering of the workpiece on the machine, but does not allow it to be finished on the same machine to remove the end technological protrusions of the workpiece necessary to install it in the centers of the machines during machining, for example , in turning or milling machines, machines for polishing, drilling and other machines.

A technical solution of the machine for finishing the head of the toe and the back of the shoe pads is known, which consists in removing technological protrusions from them, in which the automatic processing of the toe and the back of the pad is carried out due to the positioning system and the reciprocating movement of the workpiece in interaction with the processing tool (CN, 102794507 , BUT). The machine tool contains: a rack equipped with a positioning device; chopper of the head of the toe and chopper of the back, made in the form of ring mills with profiled teeth; a guide frame formed in such a way that the hydraulic cylinder of the sock head chopper is in communication with the guide frame reciprocating along the slide rail and moves the first ring tool until it contacts the shoe head; a guide plate formed so that the hydraulic cylinder of the hench chopper is connected to the guide plate, and which can slide up and down along the surface of the end of the shoe back so as to move the second ring tool until it contacts the end of the shoe shoe. However, this machine is designed to perform only one technological operation, which requires the installation of each block separately, as well as adjusting the machine with adjusting the positioning device depending on the size of the block along the length and shape of the tip of the toe and back to ensure the necessary correspondence to the position of each ring milling cutter pad position.

A known method of processing shoe pads, including the operation of removing technological protrusions of the front bow and back of the shoe in several operations in a CNC machining center (EP, 1466711, A1). The processing method includes: manually securing the pads for the indicated technological protrusions in coaxial mounts for rotating the block in a horizontal position; rough processing of the outer surfaces of the rotating workpiece; subsequent drilling of the hole at the top of the block, piercing and marking the block in its stationary horizontal position; manually removing the shoe from the fasteners and manually installing the shoe in a vertical position by pressing it onto cylinders that are hydraulically driven through a console that can be rotated around a horizontal axis; subsequent removal of the indicated technological protrusions by a rotary drill, first on the head of the front of the shoe, and then on the back of the shoe, when moving the shoe left and right in a vertical position with the corresponding console position. Thus, the specified technological process of processing includes several auxiliary transitions and several settings and settings of the processing center.

Known technical solution of the machine for finishing shaped surfaces of asymmetric shoe pads (EP, 1044622, A1), containing:

- a rotating drive head and a journal of the shank mounted coaxially on the slide moving forward and / or back to clamp or release the pads;

- a milling head for modeling and finishing the outer surface of the pads, rotated by the specified head in contact with the intended internal cavities on the back surface of the pads;

- a pin in contact with the internal cavity on the protruding front surface of the forefoot;

- two pairs of mutually orthogonal clamps:

- the first clamp mounted on an additional slide, parallel to the slide carrying the specified rotating head, and moving to the block for clamping the block in the area between the base of the heel and the edge of the back;

- the second clamp mounted on an additional slide, parallel to the slide bearing the pin, and moving to the block for clamping the block on the sides at a distance from the toe of the block;

- a second milling head with cutting edges oriented perpendicular to the cutting edges of said first milling head; - means for returning the slide of the indicated rotating head of the drive and the specified trunnion for entering them from the block at the end of modeling the block using the first milling head and after blocking the block in the same position by means of the specified pair of orthogonal clamps, while the gripping tabs of the second clamp are slightly divorced, and two gripping paws of the first clamp act on the contact points with a moment that pushes the block all the way into the divorced paws of the second clamp.

When immobilizing the shoe in the same position in which it was held by the rotating drive head and pin, the device of the drive head and machine pin can be released from the shoe, thereby allowing the front toe-shaped protrusion to be removed with the same cutter used to finish the shoe, and at the same time removal of the nose protrusion by the first cutter is performed until the specified pin comes into contact with the front surface of the nose protrusion. The rear protrusion is removed by a second additional cutter intentionally installed in the machine, the orientation of the cutting edges of which is perpendicular to the orientation of the cutting edges of the main or main mill of the machine.

However, due to the fact that the immobilization of the block in a stationary position is performed by simultaneously blocking the front of the block from moving it towards the main mill of the machine and blocking the back of the block from moving it towards the additional mill by placing the block in a certain position between the gripping legs of the first and the second clamps, open in orthogonal directions according to the placement of the cutting edges of the cutters, this installation requires high accuracy of mutual positioning The milling cutters and the contact points of the pads with the clamp legs. The displacement of the axis of the cutter and / or the deviation of the position of the contact points on the block will cause a torque that causes the block to rotate with the block leaving the tabs. In addition, when placing the shoe only in the clamps, the construction of the first and second clamps does not allow the shoe to be rotated for the subsequent finishing of the shaped surfaces of the toe and back of the shoe and for any other finishing operations.

Disclosure of invention The aim of the present invention was to develop a method for performing a complex of technological operations of machining a workpiece for the manufacture of an asymmetric product on one machine from one installation, with increasing productivity of the machine by reducing the number of auxiliary transitions, eliminating manual operations to reinstall the workpiece, and automating operations.

When creating the present invention, the technical task was posed to develop a method for the complete machining of an asymmetric workpiece to obtain an asymmetric shape product on one machine while securing the workpiece, ensuring the stability and accuracy of its original installation while applying cutting forces in different directions to different parts of the workpiece when it is roughing, including the formation on the workpiece of the necessary technological elements at the ends and lateral surfaces of the workpiece and such recesses and projections as well as its finishing, including the removal of the technological elements at its ends, and finishing after removal technological elements and creating a machine for implementing such a method. At the same time, the task was to develop an additional device for installing the workpiece during machining, providing the possibility of its rotation when changing its initial fastening on the machine with ends to fasten along the side surfaces while maintaining the initial axial orientation of the workpiece and the accuracy of its installation.

In this case, the expected technical result was the provision of the installation of the workpiece on the machine in a given initial position in various machining operations performed on the same machine, and the stability of the workpiece and the initial accuracy of its installation when interacting with the cutting tools used.

The problem was solved by creating a device for fixing an asymmetric workpiece in the machine during its machining, ensuring the preservation of the initial installation of the workpiece along the axis of the centers of the machine and containing:

- two parallel to each other and parallel to the axis of the centers of the machine rectilinear guides adapted for their placement between the attachment points of the centers of the machine; - devices for capturing the workpiece, at least in the plane of one of its cross sections, having an inner cage located in the outer casing, configured to rotate around the axis of the machine centers, and provided with at least one side of the cage with lateral circular guides on which are placed with the possibility of their angular positioning on the cage radial clamps having protruding inside the cage clamping heads made with the possibility of their movement in these radial clamps to a position about providing fixing the workpiece in the clamps with the same pressure efforts of the clamping heads on the side surface of the workpiece in the specified cross section of the workpiece,

and while the outer casing is connected by a rod with a drive of its linear movement and mounted on these two straight guides with the possibility of its movement along them in the longitudinal direction;

- control units for linear actuators of rods, drives for rotation of clips, actuators for angular positioning of radial clamps, actuators for linear movement of clamping heads and pressure sensors for head pressure on the workpiece, adapted for their connection with a numerical control device of the machine, and power supplies for these drives.

Moreover, according to the invention, rotary synchronous motors may be included as rotation drives of the cage.

The problem was also solved by creating a CNC machine for machining an asymmetric workpiece containing at least:

- bed;

- front and rear headstock with rotating centers for securing the workpiece when it is installed in the initial position with the ends in the centers of the machine;

- a support made with the possibility of its movement along the guides of the machine parallel to the axis of the centers of the machine, adapted to fix the working shafts of the cutting tools in it and give them a translational or rotational movement of cutting and translational movement of the tool into the workpiece processing zone;

- control units for a drive of linear displacement of the centers and a drive of rotation of the centers, a drive of linear displacement of the support along the guides, a rotation drive of a cutting tool, a feed drive of a cutting tool, adapted for connecting them to a machine numerical control device, and power supplies for said drives;

characterized in that the machine further comprises a device for securing the asymmetric workpiece in the machine, providing during its machining the preservation of the position of the initial installation of the workpiece along the axis of the centers of the machine, containing:

- two parallel to each other and parallel to the axis of the machine centers rectilinear guides, fixed with ends in the front and rear headstock;

- devices for capturing the workpiece, at least in the plane of one of its cross sections, having an inner cage located in the outer casing, configured to rotate around the axis of the machine centers, and provided with at least one side of the cage with lateral circular guides on which are placed with the possibility of their angular positioning on the cage radial clamps having protruding inside the cage clamping heads made with the possibility of their movement in these radial clamps to a position about providing clamping of the workpiece in the clamps with the same pressure efforts of the clamping heads on the side surface of the workpiece in the specified cross-section of the workpiece, and while:

- the outer casing is connected by a rod with a linear displacement drive located in the front or rear headstock and mounted on these two straight guides with the possibility of its movement along them in the longitudinal direction;

- each of these gripping devices is placed in the machine with the ability to change its initial position around one of the centers of the machine during initial installation of the workpiece along the axis of the machine centers with the ends in the centers of the machine to the working position around the workpiece between its ends, of which at least one end to be released from the center of the machine, which provides for positioning of the clamping heads of at least one gripper in planes of at least one cross section of the workpiece close to the processing zone;

- remote control units for linear actuators of rods, actuators for rotation of the cage, actuators for angular positioning of radial clamps, actuators for linear movement of clamping heads and pressure sensors for pressure on the workpiece, adapted for their connection with the numerical control device of the machine, and power supplies for these drives.

The task was also solved by the development of a machining method to obtain an asymmetric shape product from one installation of an asymmetric workpiece, in which processing is performed on the specified machine according to the invention described above, and at least the following actions are performed sequentially:

- make the installation of the workpiece in the initial position on the axis of the centers of the machine by abutting the workpiece with the ends against the rotating centers of the machine with the capture devices allocated for the centers of the machine;

- perform positional processing of the side surface of the workpiece to a predetermined size and shape in each of the operations, ensuring the placement of the used cutting tool in the processing zone of the workpiece and the implementation of the main cutting movements and auxiliary feed movements;

- translate the capture device in the working position around the side surface of the workpiece between its ends by moving the capture device along two of their guides, place the capture device near the intended processing zone, clamp the workpiece with the clamping heads of the radial clamps of the capture device with a constant initial position of the workpiece along the axis of the machine centers,

- release from the centers the ends of the workpiece stably gripped by the clamping heads;

- perform positional processing of the end surfaces of the workpiece to a given size and shape in each of the operations, providing placement used cutting tools in the workpiece processing zone and the implementation of the main cutting movements and auxiliary feed movements;

- release the processed part from the specified capture devices, retracting the clamping head into the radial clamps of the capture devices of the workpiece, and remove the capture device from the processing zone.

Moreover, according to the invention, the processing of one and the other ends of the workpiece can be performed sequentially or simultaneously.

Moreover, according to the invention, it is advisable to carry out the capture device on both sides of the intended cutting zone for carrying out the operation of dividing the workpiece into the right and left parts in the processing zone.

Brief Description of the Drawings

The invention is further illustrated by examples of its implementation and the accompanying drawings, in which:

Figure 1 - device for fixing an asymmetric workpiece according to the invention, appearance;

Figure 2 - device for fixing an asymmetric workpiece according to the invention, view A in figure 1;

Fig.Z - CNC machine for machining an asymmetric workpiece, appearance;

Figure 4 - diagram of the installation of the asymmetric workpiece in its original position by fixing in the centers of the machine;

Figure 5 - diagram of the processing of the workpiece when fixing in the centers of the machine;

6 is a diagram of the movement of the capture devices of the workpiece in the working position; 7 is a diagram of the placement of capture devices on an asymmetric workpiece;

8 is a diagram of the release of the workpiece from the centers;

Fig.9 is a processing diagram of the end face of the workpiece;

Figure 10 - placement of capture devices on both sides of the processing zone of the workpiece shoe pads;

11 - placement of capture devices on both sides of the processing zone when drilling holes;

Fig - placement of capture devices on two sides of the processing zone when cutting the workpiece into two parts; FIG. 13 - separation of the cut parts of the workpiece from each other while maintaining their fixation in the position of the initial installation of the workpiece.

While the above examples are not exhaustive, do not go beyond the scope of the claims and do not limit the present invention.

Best Mode for Carrying Out the Invention

The invention is further illustrated by examples of the implementation of the device according to the invention for fixing an asymmetric workpiece or an asymmetric workpiece to a machine according to the invention and a method for machining first an initial workpiece and then a workpiece on a single machine, and for the convenience of presentation, the term "workpiece is used to indicate the workpiece and workpiece ".

The device according to the invention for fixing an asymmetric workpiece while maintaining the initial installation of the workpiece along the axis of the centers of the machine is designed to be installed in a CNC machine, for example, CNC, for machining and, as shown in Figs. 1,2,3, contains two straight guides 1 and 2, parallel to each other and parallel to the axis 3 of the centers of the machine and adapted for their placement between the attachment points of the centers of the machine. On straight guides 1 and 2 are mounted with the possibility of moving along them in the longitudinal direction two capture devices of the workpiece: device 4A capture the left side of the workpiece and device 4C capture the right part of the workpiece.

Each workpiece gripping device 4a, 4c has an outer casing 5 (Fig. 1,2) connected by a rod 6a or 6c, respectively, with a linear drive of the headquarters (not shown in the drawings) having its control unit (not shown in the drawings), connected to the CNC device of the machine. The movement of the rods 6a and 6c provides the movement of the outer casing 5 of the devices 4a, 4c of gripping the workpiece along the guides 1 and 2.

In the outer casing 5 of the workpiece gripping devices 4a, 4c, an inner sleeve 7 is installed (Figs. 1 and 2), arranged to rotate around the axis 3 of the machine centers from the drive (not shown), which can be used as a rotary synchronous motor located in the outer casing 5. The inner cage 7 is provided with lateral circular guides 8, for example, on one side of the cage 7, as shown in FIG. 2, or on both sides of the cage 7, for example, as shown in FIG. 1, and comprises a drive power unit 7a.

On the lateral circular guides 8 there are placed radial clamps 9, for example, three radial clamps 9 on one side of the cage 7 (Fig. 3), or three radial clamps 9 on one and on the other side of the cage 7 (Fig. 1) with the possibility of their angular positioning on the clip 7 drive (not shown), depending on the shape of the workpiece or the workpiece.

The radial clamps 9 have clamping heads 10 protruding inwardly of the sleeve 7, arranged to move them in said radial clamps 9, for example, by a hydraulic cylinder actuator 9a, against the stop on the side surface of the workpiece with the same pressure forces of the clamping heads 10 on the side surface of the workpiece, controlled by sensors 1 1 pressure efforts of the heads on the workpiece, adapted for their connection with the CNC machine tool.

The set of contact points of the workpiece with the clamping heads 10, placed on the circular guides 8 on one side of the cage 7, determines the plane of its clamp on the side surface. When performing gripping devices 4a, 4c with cages 7 containing circular guides 8 on both sides of the casing 7, the workpiece is secured by each gripping device 4a, 4c in two closely located clamp planes, which increases the stability and accuracy of its fastening with the initial position relative to axis 3 machine centers.

The operation of the device for securing the workpiece according to the invention is ensured by the submission of commands from the CNC device of the machine. On command from the machine’s CNC device to the power supply units of these drives in a given sequence, the rods 6a and / or 6c are moved until the devices 4a and / or 4c reach the set position on the rails 1 and 2, the angular positioning of the radial clips 9 on the clip 7 is provided, the extension clamping heads 10 all the way to the side surface of the workpiece with the same pressure force controlled by the sensors 11 at each point of contact of the clamping head 10 with the workpiece. This ensures that the position of the workpiece on the axis 3 of the centers of the machine. When a command is sent from the machine’s CNC device to the control unit for the rotation drive of the cage 7, the cage 7 rotates in the outer case 5, providing rotation of the clamping heads 10 and the workpiece on the axis of rotation of the cage 7, pine with the axis 3 of the centers of the machine.

Thus, fixing the workpiece in its initial position with the possibility of rotation during the entire cycle of its machining provides the possibility of using CNC to automatically change the fixing scheme of the workpiece for processing previously inaccessible end surfaces when changing its initial fastening on the machine with the ends to be fixed along the side surfaces while maintaining the initial axial orientation of the workpiece and the accuracy of its installation, eliminates the reinstallation of the workpiece when changing the cutting tool, lawsuit to facilitate intermediate adjustment of the machine, thereby increasing the productivity of the machine.

Fig. 3 shows schematically a CNC machine according to the invention for machining an asymmetric workpiece to obtain an asymmetric shape product from one installation in which the device according to the invention is mounted for fixing an asymmetric workpiece.

The machine includes a bed 12 and front 13 and rear 14 of the headstock with rotating centers 15 for securing the workpiece 16 when it is installed in the initial position along the axis 3 of the machine centers with the ends 17 and 18 in the centers 15 of the machine (Fig.Z).

The machine contains a support 19, made with the possibility of its movement along the guides 20 of the machine parallel to the axis 3 of the centers 15 of the machine, adapted to fix the working shafts of cutting tools, for example, the milling head 21 (Fig.Z), and give them a translational or rotational cutting movement and translational movement of the tool feed into the processing zone 22 of the workpiece 16 and the withdrawal of the tool from it. In this case, the support 19 may contain the necessary set of cutting tools, ensuring the implementation of a full range of machining operations. An additional support can also be used with a different direction of tool feed and a different direction of workpiece cutting forces, but securing the workpiece in the device according to the invention provides stability and accuracy of installation of the workpiece in this case. In the front 13 and rear 14 headstock of the machine, two guides 1 and 2 of the device are fixed for fixing the asymmetric workpiece, and rods 6a and 6c are installed with their linear displacement drives and control units rigidly connected to the external bodies 5 of the workpiece gripping devices 4a, 4c, respectively (Fig. .3).

The sequence of machining operations while maintaining its installation in the initial position relative to the axis of the centers of the machine is shown schematically in FIG. 4-9.

Each of these capture devices 4a, 4c is placed in the machine with the possibility of changing the initial position of its outer casing 5 around one of the centers 15 of the machine during initial installation of the workpiece 16 along the axis 3 of the machine centers with the ends 17 and 18 in the centers 15 of the machine (Figure 4) on the working position of the outer casing 5 around the initial processing cycle of the workpiece 16A between its ends 17 and 18 near the zone of the proposed subsequent processing of the ends (Fig.7).

At the same time, in the working position, the gripping devices 4a, 4c can be placed with each other at different distances necessary to maintain the accuracy of installation of the workpiece 16 when applying cutting forces in different directions both at the ends 17,18 and in the middle part of the workpiece 16, which allows use the device according to the invention for fastening a long asymmetric workpiece while maintaining the fixation of the other end face of the workpiece in another fixture available in the machine for fixing, for example, a pin.

For sequential or simultaneous processing of the ends of the workpiece, the gripping devices 4a, 4c can be applied sequentially one after the other or both simultaneously. In this case, during positional processing of the workpiece 16, these clamping heads 10 of at least one of the gripping devices 4a, 4c are arranged in the plane of at least one cross-section of the workpiece 16 close to the processing zone.

The machine according to the invention also contains control units for a drive of linear movement of the centers 15, a drive for rotation of the centers 15, a drive for linear movement of the support 19 along the guides 20, a drive for rotation of the cutting tool, a drive for feeding the cutting tool, and also control units for drives for linear movement of the rods 6, rotation drives of the holders 7, angular positioning drives radial clamps 9, linear drives the movement of the clamping heads 10 and the sensors 11 of the pressure forces of the clamping heads 10 on the workpiece, adapted for their connection with the CNC machine tool, and power supplies of these drives.

Thus, the machine according to the invention provides the ability to perform fastening operations, working motions and feed motions necessary to perform complete machining of the asymmetric workpiece to obtain the finished product of an asymmetric shape when the workpiece 16 is installed on the machine in the same predetermined initial position relative to the axis 3 of the centers the machine, regardless of the scheme of its fastening in the machine, with a different arrangement on the same machine of different cutting tools, and maintaining the stability of the workpiece ki and the initial accuracy of its installation when it interacts with the cutting tools used.

The method of machining an asymmetric workpiece to obtain an asymmetric shape product from one installation is further presented on the example of the manufacture of an asymmetric shoe shoe made of wood on a CNC machine according to the invention.

The method includes sequentially performing at least the following actions shown in FIG. 4-9:

1) the workpiece 16 is installed in its initial position on the axis 3 of the machine centers by stopping the workpiece 16 with the ends 17 and 18 of the rotating centers 15 of the machine, having previously provided the position of the gripping devices 4a, 4c behind the centers 15 of the machine by actuating the linear actuators of the rods for 6 s capture devices 4a, 4c by the CNC command to the leftmost and rightmost positions, respectively (Figure 4);

2) perform positional processing of the workpiece 16 to a predetermined size and shape in each of the working operations, ensuring the placement of the used cutting tool in the workpiece processing zone 22 by moving the support 19 along the machine guides 20 and performing basic cutting movements and auxiliary cutting movements of the cutting tool into zone 22 processing the workpiece 16 and the output of the tool from it (Figure 5);

3) transfer the capture devices 4a, 4c to the working position around the side surface of the workpiece 16a between its ends 17 and 18 by moving the devices 4a, 4c capture along two of their guides 1, 2 when moving the rods 6 (Fig.6); place capture devices 4a, 4c near the proposed cutting zone 22; clamping the workpiece 16a by the clamping heads 10 of the radial clamps 9 of the gripping devices 4a, 4c, while maintaining the initial position of the workpiece 16a along the axis 3 of the machine centers (Fig. 7);

4) release previously fixed in the centers 15 of the ends 17 and 18 of the workpiece 16A, stably grasped by the clamping heads 10 (Fig.8);

5) perform sequentially or simultaneously positional processing of the surfaces of the workpiece 16a, captured by the clamping heads 10, to a predetermined size and shape in each of the working operations, ensuring the placement of the used cutting tool in the processing zone 22 and the execution of the main cutting movements and auxiliary feed movements (Fig. 9 );

6) release the processed part from these gripping devices 4a, 4c by moving the clamping heads 10 inside the radial clamps 9 of the workpiece gripping devices 4a, 4c.

When implementing the method of machining an asymmetric workpiece according to the invention in a machine according to the invention, comprising a device for securing an asymmetric workpiece according to the invention, it is possible to carry out a wide range of working operations on one machine, including all types of turning, as well as milling, drilling, boring and other working operations as on the side and end surfaces of the workpiece, for example: machining off-center holes, milling flats, keyways, shaped grooves, longitudinal and transverse planes, profile grooves and other elements, drilling holes, through firmware, and other operations.

Figure 10-13 shows the placement of capture devices 4a, 4c, each having on each side of the cage 7 three radial clips 9 with clamping heads 10 arranged in four cross sections of the shoe shoe blank, two sections at a distance from each other on both sides from the proposed processing zone, with the formation between them of the processing zone 22 when capturing the toe and heel of the shoe: after the milling operation of the toe and heel of the workpiece is performed in the processing zone 22 (Figure 10); after performing a drilling through hole 23 in the processing zone (FIG. 11); after performing in zone 22 processing cutting blocks with a disk cutter into two parts with the retention of each part in the corresponding devices 4A, 4C capture (Fig). 13 shows the separation of the cut parts of the workpiece from each other by moving the gripping devices 4a, 4c in opposite directions while maintaining the stability and reliability of securing each part in the gripping devices 4a, 4c, which allows further processing of each part of the block separately.

Thus, the method for machining an asymmetric workpiece according to the invention in a CNC machine according to the invention, comprising a device for securing an asymmetric workpiece according to the invention, enables various machining operations from one workpiece installation to its initial position and the ability to automatically control cutting tools, attachment and moving devices .

The proposed technical solution for processing parts from one installation allows you to make a finished part on one machine. At the same time, the design of the machine allows you to add the necessary components and devices for the most complete execution of specific tasks of machining the part.

So, for example, for the manufacture of a hanger hanger, a grinding unit in the form of a sanding belt or a flap grinding disc, which follows the cutter, can be additionally installed on the machine, an additional milling unit for the production of a connecting stud on the workpiece. With a sufficient number of additional milling units and accessories, one machine according to the invention can replace five separate machines (band saw, milling, trimming, tenoning, grinding), which saves time on each installation of the part, increases the accuracy of processing, eliminates manual labor. Accordingly, the production area is saved, the “path” of the part is reduced, unloading, loading, stacking, transportation from machine to machine are eliminated, energy is saved (for turning on engines, for lighting workplaces), work safety is improved due to cassette loading of blanks and automatic unloading machined parts.

The CNC machine according to the invention allows its modification. For example, in the manufacture of shoe pads there is no need to add a grinding unit (when using blanks made of polyethylene), but it is advisable add two drilling and additive units for the production of technological holes necessary for the subsequent fixation of the device “folding” pads. When using paired clamps for fixing workpieces of shoe pads, the technological scheme of processing changes with a decrease in the machine park from the already possible seven machines to nine. In this case, manual labor is completely excluded. Production can be completed with one machine (for small workshops and ateliers of individual sewing), as well as any necessary number of machines for large factories. Moreover, unlike the existing multi-spindle (8-12) machines, the machine according to the invention does not have manual installation of parts, which allows to increase the working time of the machines. In addition, the overall working time of personnel during machine maintenance is saved.

With the further development of the tooling system, the principle of the processing method according to the invention allows the use of workpieces not only from wood and plastic, but also from other materials.

It is possible to use air motors constructively, which will improve aspiration, cooling of the cutting tool and increase fire safety.

Thus, the technical solutions of the method of machining an asymmetric workpiece from one installation according to the invention, a CNC machine according to the invention and a device for fixing the workpiece according to the invention has significant advantages in the method of processing products in comparison with known methods.

Industrial applicability

The device for fixing an asymmetric workpiece according to the invention and a CNC machine according to the invention can be made of known materials and components using known technologies and can be widely used in the mass production of asymmetric shaped products with shaped surfaces from various materials.

Claims

Claim

1. A device for fixing an asymmetric workpiece in the machine during its machining, ensuring the preservation of the position of the initial installation of the workpiece along the axis (3) of the centers of the machine, containing:

- two parallel to each other and parallel to the axis of the machine centers rectilinear guides (1.2), adapted for their fastening between devices (13,14) for fastening the centers (15) of the machine;

- devices (4a, 4c) for gripping the workpiece, at least in the plane of one of its cross sections, having an inner cage (7) located in the outer case (5), configured to rotate around the axis (3) of the machine centers, and provided at least on one side of the cage (7) with lateral circular guides (8), on which radial clamps (9) having clamping heads (10) protruding inwardly of the cage (7) are placed with the possibility of their angular positioning on the cage (7) made with the possibility of their movement in the indicated radial clamps (9) to a position that secures the workpiece (16) in the clamps (9) with the same pressure forces of the clamping heads (10) on the side surface of the workpiece (16) in the specified cross-section of the workpiece, and the outer case (5) is connected by a bar (6a, 6c) with a drive of its linear movement and is mounted on the indicated two rectilinear guides (1,2) with the possibility of its movement along them in the longitudinal direction;

- control units for actuators of linear movement of rods (6a, 6c), actuators of rotation of clips (7), actuators of angular positioning of radial clamps (9), actuators of linear movement of clamping heads (10) and sensors (11) of pressure forces of heads (10) on the workpiece (16), adapted for their connection with the machine numerical control device, and power supplies of these drives.

2. The device according to claim 1, characterized in that the rotation drives of the cage (7) contains rotary synchronous motors.

3. A CNC machine for machining an asymmetric workpiece to obtain an asymmetric shape product from one installation, containing at least:

- bed (12);

- front (13) and rear (14) headstock with rotating centers (15) for securing the workpiece (16) when it is installed in the initial position with the ends (17.18) in the centers (15) of the machine;

- a support (19) made with the possibility of its movement along the guides (20) of the machine parallel to the axis (3) of the centers of the machine, adapted to fix the working shafts of the cutting tools in it and give them a translational or rotational movement of cutting and translational movement of the tool into the zone ( 22) processing the workpiece and output from it;

- control units for the drive of linear movement of the centers (15) and the drive of rotation of the centers (15), the drive of linear movement of the caliper (19) along the guides (20), the rotation drive of the cutting tool, the feed drive of the cutting tool, adapted for connecting them to a numerical control device machine, and power supplies of these drives;

characterized in that:

- additionally contains a device for fixing an asymmetric workpiece in the machine, providing during its machining preservation of the initial installation position of the workpiece along the axis (3) of the centers of the machine, containing:

- two parallel to each other and parallel to the axis of the machine centers rectilinear guides (1,2), fixed by the ends in the front (13) and rear (14) headstock;

- devices (4a, 4c) for gripping the workpiece, at least in the plane of one of its cross sections, having an inner cage (7) located in the outer case (5), configured to rotate around the axis (3) of the machine centers, and provided at least on one side of the cage (7) with lateral circular guides (8), on which radial clamps (9) having clamping heads (10) protruding inwardly of the cage (7) are placed with the possibility of their angular positioning on the cage (7) made with the possibility of their movement in the indicated radial clamps (9) to a position that secures the workpiece (16) in clamps (9) with the same pressure forces of the clamping heads (10) on the side surface of the workpiece (16) in the specified cross section of the workpiece, and wherein:

- the outer casing (5) is connected by a rod (6a, 6c) with a linear displacement drive located in the front (13) or rear (14) headstock and mounted on these two straight guides (1,2) with the possibility of its movement along them in the longitudinal direction;

- each of these capture devices (4a, 4c) is placed in the machine with the possibility of changing its initial position around one of the centers

(15) of the machine during the initial installation of the workpiece (16) along the axis (3) of the centers of the machine with the ends (17,18) in the centers (15) of the machine to the working position around the workpiece

(16) between its ends (17,18), of which at least one end is to be released from the center of the machine, which ensures positioning of the clamping heads (10) of at least one device (4a, 4c) when positioning the workpiece ) capture in the plane of at least one cross section of the workpiece (16) close to the processing zone (22);

- remote control units for linear actuators of rods (6a, 6c), rotational drives of a cage (7), angular positioning drives of radial clamps (9), linear actuators of clamping heads (10) and sensors (11) of head pressure on the workpiece, adapted for their connection with the machine numerical control device, and power supplies for these drives.

4. The machine according to claim 3, characterized in that as the drives for rotating the cage (7) of the workpiece gripping devices (4a, 4c) comprises rotary synchronous motors.

5. A method of machining an asymmetric workpiece to obtain an asymmetric shape product from one installation, in which the processing is performed on a machine according to any one of claims 3 to 4, and at least the following actions are performed:

- the workpiece is installed (16) in the initial position on the axis (3) of the machine centers by stopping the workpiece with the ends (17,18) in the rotating centers (15) of the machine with the gripping devices (4a, 4c) allocated for the centers (15) of the machine;

- perform positional processing of the side surface of the workpiece (16) to a predetermined size and shape in each of the operations, providing placement used cutting tool in the zone (22) processing the workpiece and the implementation of the main cutting movements and auxiliary feed movements;

- transfer capture devices (4a, 4c) to the working position around the side surface of the workpiece (16a) between its ends (17,18) by moving the capture devices (4a, 4c) along their two guides (1,2), place devices (4a 4c) gripping near the proposed processing zone (22), clamp the workpiece (16a) with the clamping heads (10) of the radial clamps (9), while maintaining the initial position of the workpiece along the axis (3) of the machine centers;

- release from the centers (15) the ends (17.18) of the workpiece stably gripped by the clamping heads (10);

- perform positional processing of the end surfaces of the workpiece (16a), captured by the clamping heads (10), to a predetermined size and shape in each of the operations, ensuring the placement of the used cutting tool in the workpiece processing zone (22) and performing the main cutting movements and auxiliary feed movements ;

- release the processed part from the specified capture devices (4a, 4c) by pulling the clamping heads (10) into the radial clamps (9), and take the capture devices (4a, 4c) out of the processing zone (22).

6. The method according to claim 5, characterized in that the processing of the ends of the workpiece is carried out sequentially.

7. The method according to claim 5, characterized in that the processing of the ends of the workpiece is carried out simultaneously.

8. The method according to claim 5, characterized in that for carrying out in the processing zone (22) the operations of dividing the workpiece (16a) into the right and left parts by milling of the gripping device (4a, 4c) are placed on both sides of the intended processing zone.