RU176638U1 - TAPE-CUTTING MACHINE - Google Patents

Abstract

The utility model relates to the field of machine tool industry, namely to the device of horizontal band-cutting machines designed to separate various materials of uniform cross section (rods) into parts and having one or more guide columns (racks). The machine comprises a supporting frame 1, on vertical racks of which in the bearings of bearings 2 are fixed ball screw pairs 3 (ballscrews), linear guides 4 and measuring rulers 5. Ballscrew nuts are connected to the carriages 6 of the linear guides through the bracket 7. The frame rotates on the shaft 8 relative to the table 9 The shaft of the frame 8 enters the hole in the table 9 and is installed in the rotation unit 10. There is a thread at the end of the shaft. The frame is fixed to the table using the lever 11 having a reciprocal thread by pressing. Ball screw pairs 3 are connected through couplings 12 to the drive devices 14. The drive devices are attached to the carrier frame on the bracket 15. The control is carried out from the control cabinet 16. The working module 17 is pivotally mounted on the carriages 6 of the carriages. It can rotate relative to the first carriage of the carriage and rotational-translational motion relative to the studs of the second carriage. Due to this, the working module is simultaneously moved and makes swinging movements in a vertical plane. The housing of the working module 17 is used for fastening the rotating wheels 18, the tension system of the band saw 19, the gear motor 20, the guides of the band saw, automation elements, the supply system of COTS (cutting fluid). The band saw 21 is mounted with its teeth down on the wheels to the stop in the flanges of these wheels and tensioned using the tension system 19. It is deployed with the help of guides into the feed (cutting) plane 22 and is perpendicular to the working surface of the table. In this case, the axis of the shaft of the supporting frame 1 is in the supply plane 22. The workpiece 23 is located on the feed table 24 and fixed motionless in a vise 25. The design of the band-cutting machine allows you to implement various modes of operation due to a wide range of automatic and manual settings of geometric and physical parameters of the cutting process, which ultimately increases productivity and efficiency.

Description

The utility model relates to the field of machine tool industry, namely to the device of horizontal band-cutting machines designed to separate various materials of uniform cross section (rods) into parts and having one or more guide columns (racks).

It is known from the prior art that band-cutting machines have a bed or table on which two columns (racks) are most often vertically mounted. A working module consisting of a frame containing a driven and driving pulleys moves along the columns, as along the guides.

The working module is moved by a hydraulic or electromechanical drive, which ensures its lowering at a given speed (feed). The feed is adjustable. On the pulleys with the help of a tension device, a band saw is fastened with its teeth down. The drive pulley is driven by a gear motor. Due to this, the band saw makes a circular motion on the pulleys. Changing the speed of the drive pulley affects the speed of the band saw and is also adjustable. In the area between the pulleys, the band saw blade moves rectilinearly. On the working module there are also devices for supplying cutting fluid, tensioning the band saw, devices for turning the band saw into the cutting plane (feed). The working section of the band saw is located horizontally or with a slight slope relative to the horizontal surface of the table (bed) and is not able to change the angle of inclination in the plane of sawing (feed).

In this case, the working module with a moving band saw moves down the guide columns.

In most of the known designs of band-cutting machines during operation, the geometry of the section of the cut bars is not taken into account, since this requires the use of new kinematic schemes.

On the other hand, it is known that sawing rods with different cross-sectional shapes, but with the same area, takes different time and power consumption, because depending on the shape of the cross-section of the bar at different times, a different number of band saw teeth is involved in the work.

Thus, taking into account the cross-sectional shape of the bar being cut and adjusting the feed rate, the speed and inclination of the band saw, it is possible to increase the performance of the band-cutting machine, especially when sawing rods of large diameters and difficult to process materials.

A known design of a band-cutting machine in the description of patent JP 2015-155122 A of 08.27.2015, allowing to implement cutting methods using the inclination of the band saw. Disadvantages of this

designs are:

- low rigidity due to the presence of one guide column,

- the inability to select the cross-sectional shape of the cut rod (blank W),

- the design is complicated by the fact that a hydraulic actuator is used, which contributes its energy loss to convert electrical energy into transmission pressure,

- there is no possibility of rotation of the band saw relative to the axis of the guide column.

The band cut-off machine closest in design and sawing method is considered in the patent under the number US 4579026 from 01/01/1986

In this utility model, a cutting method is used by moving the run-in of a workpiece with a band saw. This prototype has the following disadvantages compared with the proposed utility model:

- low cutting speed, since the movement of the band saw is tangential to the arc and only at the extreme points at the time of cutting into a given step - progressively. The length of the cutting path is significantly increased, which affects the cutting time.

- the movement of the working module with a moving band saw does not depend on the dimensions and cross-sectional shape of the cut bar.

- there is a need for the manufacture or selection of the geometry of the cams, curved arcuate guides used to copy movements with a working tool (band saw).

- the design is complicated by the fact that in these cases a hydraulic drive is used, which contributes its energy losses to the conversion of electrical energy into transmission pressure.

- there is no possibility of turning the band saw and cutting at a given angle relative to the longitudinal axis of the cut bar.

The proposed utility model is aimed at increasing the cutting speed of workpieces with high physical and mechanical properties and workpieces with large cross-sectional areas, improving the quality and surface accuracy of the parts to be separated, extending the service life of the band saw due to the rigid structure of the carrier frame, the method of attaching auxiliary elements to it (layout), the design of the working module and the implementation of modes of operation with a variable inclination of the band saw.

The objectives of the utility model is to increase the productivity of the tape-cutting machine, increase efficiency, reduce material consumption.

The technical result is an increase in the sawing speed of workpieces with high physical and mechanical properties and workpieces with large cross-sectional areas, extending the service life of the band saw.

The technical result is achieved due to the rigid structure of the supporting frame, the method of mounting auxiliary elements (layout) on it, the kinematic scheme for changing the angle of inclination of the working module and the band saw with it, as well as the implementation of various operating modes taking into account the use of the kinematic scheme.

The essence of the utility model is illustrated by drawings, which depict:

in FIG. 1 - tape cutting machine, general view;

in FIG. 2 - tape cutting machine, side view;

in FIG. 3 - sketch of the supporting frame;

in FIG. 4 - bearing frame assembly;

in FIG. 5 is a kinematic diagram of the movement of the working module of the tape-cutting machine in the feed plane (front view);

in FIG. 6 - horizontal groove on the rear wall of the working module;

in FIG. 7 is an example illustrating the operation of a band-cutting machine.

The fulfillment of the tasks is achieved through the implementation of the design of the supporting frame, support table, the fastening system of the power elements and methods for controlling the movement of the working module body in order to change the angle of inclination of the band saw in the feed plane. The design of the supporting frame 1 is rigid, on the vertical struts of which in the bearings of the bearings 2 are fixed ball screws 3 (ballscrews), linear guides 4 and measuring rulers 5. The force from the ballscrews to the carriages 6 is transmitted using brackets 7. The bearing frame with a shaft 8 fixed to it rotates relative to the support table 9 to select the desired cutting angle in the vertical plane. The shaft of the supporting frame 8 enters the hole of the support table 9 and is installed in the rotation assembly 10, consisting of a bearing housing and a bearing block. There is a thread at the end of the shaft. The supporting frame is fixed to the support table using the lever 11 having a reciprocal thread by pressing. Thus, the supporting frame with the shaft rotates relative to the support table and when choosing the cutting angle (+/- b) is fixed by the lever (Fig. 3).

Ball screw pairs 3 are connected via couplings 12 to drive means 14, for example, servomotors or stepper motors. The drive means are attached to the frame on the brackets 15. The drive means are controlled in accordance with the commands coming from the control cabinet 16 containing the control system.

On the studs of the carriages 6 a working module 17 is fixed.

The working module is capable of simultaneously translating by converting the movement of rotation of the drive means in ballscrews and swinging along linear guides by hinging one wall of the housing of the working module having a round hole on the stud of the first carriage through the aforementioned round hole and the other wall the housing of the working module having a horizontal groove on the stud of the second carriage through said horizontal groove.

With any change in the cutting angle a, the pin of the second carriage occupies the required position in the horizontal groove (Fig. 6).

The presence of the groove is due to the fact that with a change in the sawing angle, the hypotenuse of triangle C can vary from the distance between the axes of the ballscrew screws (L) to the value C = L / cos a (Fig. 5).

The value of L is constant for a particular frame size of a cutting-off machine. The value of a varies within +/- 10 ° and is limited for design reasons. It is controlled by limit switches located on one of the carriage pins (not shown in the figures).

To increase accuracy and durability, the carriage studs must be hardened and ground. In critical assemblies, the use of bearings and hardened parts is recommended.

The housing of the working module 17 is a frame that serves for mounting:

- rotating wheels 18 - driven and leading;

- devices for tensioning the band saw 19 (shown conditionally);

- gear motor 20 for rotating the drive wheel (shown conditionally);

- guide rollers of the band saw (not shown in the figures);

- automation elements (tension sensors, end sensors, etc.), (not shown in the figures);

- coolant supply system (not shown in the figures).

The band saw 21 is mounted with its teeth down on the wheels as far as the stop in the flanges of these wheels and tensioned using the tension system 19.

The band saw 21 is deployed using guide rollers (not shown) in the feed plane 22. A necessary requirement is the condition that the band saw 21 is perpendicular to the surface of the supporting table in the feed plane 22. It is important that the axis of the shaft of the carrier frame 1 is in the feed plane 22 (cutting )

The change of the band saw 21 is carried out with the working module 6 raised as high as possible with a weakened tension system 19.

The workpiece 23 is located on the feed table 24 and is fixed stationary by means of fixation, for example a vise 25.

To automate the supply and fastening of the bar, a feeder can be used, the design of which is selected from the operating conditions of the band-cutting machine.

Tape-cutting machine, arranged according to the proposed utility model, operates as follows. As an example, we consider one of the many possible modes of operation with a variable angle of inclination and a constant step shown in FIG. 7.

In this mode of operation, the following sequence of operations is performed.

After turning on the machine, installing and attaching to the cutting bar feed table, the cross-sectional shape of the bar (circle, square, rectangle) is selected.

The overall dimensions of the bar in the cross section are introduced into the control system (side dimensions - A, B).

The material to be cut is selected from the list of possible options, the number of cuts (N), the width of cut C, the brand of the band saw.

From the values stored in the database, the control system assigns the optimal cutting speed S, the feed of the cutting blade F, the angle of inclination a and the pitch (H).

Step H is determined from the angle of the band saw and the distance between the axes of the linear guides Z1 and Z2. A positive value is the movement of the band saw up.

Before starting the automatic mode, the band saw is brought to machine zeros and raised above the overall size of the bar for its free movement into the cutting zone. Machine zeros are, for example, at the level of the plane of the support table.

The bar is fed to a predetermined cutting width and fixed with mechanical, hydraulic or pneumatic means, for example, with a vice.

Turn on the band saw drive and start automatic operation.

In automatic mode, the control system performs the following sequence of actions.

It feeds horizontally a band saw simultaneously along two axes to a height of Z = A, where A is the vertical size of the workpiece.

It turns on the drive of the Z1 axis and performs sawing towards the table, until it reaches the value of step H, after which it quickly accelerates the band saw along two axes up to half a step N / 2.

Further, the control system includes a Z2 axis drive and saws with a band saw of step H towards the table, at which the cutting angle a changes to the opposite.

The control system repeats the sequence of the previous three steps until the values Z1 and Z2 reach the value "0". If Z1 and Z2 are equal to “0”, the band saw drive is turned off, and the feed drive devices move the working module with the band saw to its original position.

If the value of N (the number of cuts) is not equal to zero, then the bar is fed by the value of the width of the cut, and so on until the required number of blanks is cut off.

The experiments showed that, ceteris paribus, sawing a bar with a triangular profile in the section, starting from the top of this triangle, is performed up to 30% faster compared to a rectangular section of the same area. The highest productivity was obtained for rods with high physical and mechanical properties and for rods with a large cross-sectional value.

Claims (1)

A cutting-off machine containing a support table with a rotation unit consisting of a housing and a bearing block, a supporting frame with a shaft fixed to it and linear guides installed in its supports, ball screw pairs and linear displacement measuring instruments, carriages, on the studs of which the worker is articulated a module in the form of a housing on which a gear motor for fixing the drive wheel is fixed, a band saw tension device, drive and driven wheels, a band saw, guide rollers for turning the cutting h part of the band saw into the feed plane, means for controlling the angular position of the working module and the band saw tension, drive devices and a workpiece feed table attached to the support frame, provided with means for fixing and supplying the workpiece, characterized in that the support frame with the shaft is connected to the rotation unit of the support table and the axis of rotation of the shaft of the supporting frame lies in the plane of the feed of the band saw, while the working module is configured to provide simultaneous translational motion by converting the motion coupling drive means in ball screw pairs and swinging motion along linear guides by hinging one wall of the working module housing having a round hole on the stud of the first carriage through the aforementioned round hole, and another wall of the working module housing having a horizontal groove on the stud of the second carriage through said horizontal groove.

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