RU2356671C1 - Hand bending device - Google Patents

Abstract

FIELD: metallurgy.

SUBSTANCE: invention relates to metal deformation process field and provided for hand bending of stripe material. Facility contains basis, handle, support with matrix, puncheon, fixed in holder, connected to slider, eccentric mechanism, connected to slider. Eccentric mechanism is implemented in the form of couple of eccentrics, bearing and additional, lever-rocker with roller and rod with body. Eccentrics are implemented with different eccentricity and different diametres, at that eccentric with high diametre is implemented with higher eccentricity. Bearing eccentric is implemented with less eccentricity and nave, on which it is put additional eccentric with ability of rotation with further fixation. In eccentrics there are implemented notches, dimensions and form of which is so that notch in bearing eccentric by area in not overlapped by notch in additional eccentric.

EFFECT: facility provides contract efforts, applied by operator during the bending, provides usability of operator and with this increases efficiency of its labor, improving of manufactured cutter, increasing of device life time.

3 cl, 3 dwg

Description

The invention relates to the field of processing materials by pressure and can be used for bending strip material, including for bending scoring and chopping knives of die-cutting dies, which are used for the manufacture of packaging, labels, etc.

Known press brake with manual drive (1), containing the base, the matrix and installed with the possibility of reciprocating movement of the punch. The movement of the punch is carried out by means of a lever mechanism, which requires considerable effort on the part of the operator.

Known manual bending device (2), containing the base, matrix, punch and eccentric mechanism based on one eccentric to move it. This device allows you to reduce the effort exerted by the operator during operation, when bending one - and 2-point rulers. However, when bending 3-point and thicker rulers and bending rulers for technical dies, the operator has to make considerable efforts.

The technical result of the invention is to reduce the efforts exerted by the operator when bending, ensuring the convenience of his work and thereby increasing his productivity, improving the quality of the manufactured knife, increasing the service life of the device.

The specified technical result is achieved by the fact that in a manual bending device containing a base, a handle, an abutment with a die, a punch fixed in a holder connected to a slider, an eccentric mechanism connected to the slider, bearing bearings rigidly fixed to the base, a spring connected to base, the eccentric mechanism is made in the form of a pair of eccentrics, bearing and additional, rocker arm with a roller and a rod with a housing, the eccentrics are made with different eccentricities and different diameters, with this eccentric with a large diameter is made with a large eccentricity, the bearing eccentric is made with a smaller eccentricity and the hub and rigidly mounted on a shaft mounted in the bearing bearings, an additional eccentric is mounted on the bearing hub with the possibility of relative rotation with subsequent fixation, while the eccentrics are placed relative to each other so that the beginning of the working section of the additional eccentric coincides with the end of the working section of the supporting eccentric in the direction of rotation of the shaft; There are recesses, the dimensions and shape of which are such that the recess in the supporting eccentric is not blocked by the recess in the additional eccentric, the rocker arm is mounted on an articulated support fixed to the base, the roller is mounted at one end of the rocker arm in contact with the clowns, while the width of the roller greater than the width of the working surface of any eccentric, the second end of the rocker arm is pivotally connected to the housing, one end of the rod is pivotally connected to the slider, and the other end is placed in the housing and installed in contact with the adjusting screw ohm-abutment mounted on the wall of the housing, wherein the housing is in a threaded hole in which a screw for fixing the rod, a second end of the spring is mounted on the slider, and the handle is rigidly fixed on the shaft eccentrics.

The technological process of bending, based on the laws of metal deformation, is as follows. The entire path of the slider with the punch (with a fixed matrix) can be divided into three sections. The first, longest, slider with a punch passes until it meets a workpiece resting on a matrix. This section is necessary for preliminary auxiliary actions (tool replacement, cleaning of the working space, etc.).

In the second section, from the beginning of the interaction of the punch with the workpiece supported by the matrix, maximum force is required with minimal movement, since here it is necessary to overcome the elastic deformation of the metal (proportionality limit) and reach the level of plastic deformation (the stress in the metal must exceed the yield strength). Moreover, a high deformation rate can lead to cracks and local damage to the surface of the workpiece. The indicated section should correspond to the zone of the working profile of the eccentric adjacent to the point as far as possible from its center (apogee).

The third, final section, is characterized by almost no increment of effort, since here is the area of plastic deformation. The resulting bend of the line should ensure the achievement of the parameters of the die form. This section corresponds to the zone of the working profile of the eccentric adjacent to the region remote from the apogee.

In practice, the slide stroke at maximum force from the operator is 4-6 mm, and its total path is 20-30 mm. At the same time, the rotation angle of the eccentric associated with the handle should not exceed 130 °° according to ergonomic requirements.

This is the optimal sequence of interactions in the bending device.

In a mechanism based on one eccentric, the region of maximum force created is near the apogee, i.e. at the end of the path of the slider with the punch, where its movement is minimal. For the bending process in this section, there is no need for maximum effort (the stage of plastic deformation), but a relatively large displacement is necessary. Maximum effort and minimum displacement are required at the previous stage (elastic deformation stage). Thus, in a mechanism based on a single eccentric, overcoming the resistance to elastic deformation falls on the area remote from the climax, which requires the operator to have excessive, often impact, impacts on the handle. The negative consequences of this include the low accuracy of the bent profile and surface defects of the knife, premature wear of machine parts, and accumulated operator fatigue during the work shift, which reduces its productivity.

An eccentric mechanism based on a pair of eccentrics according to the invention overcomes these drawbacks while maintaining the necessary amount of slide movement. In such a mechanism, the maximum force and minimum displacements occur at the stage of elastic deformation of the metal, and relatively large displacements - at the stage of plastic deformation. In this case, the first section (the section before meeting with the workpiece) is overcome at a small angle of rotation of the handle (20 ° -30 °), due to the presence of a recess on the profile of the eccentric. The force here is required only to overcome the resistance of the spring.

A manual bending device is shown in figures 1-3, while figure 1 shows a schematic kinematic diagram of a device where

1 - base

2 - slider

3 - holder

4 - punch

5 - top cover of the base,

6 - emphasis

7 - matrix

8 - supporting clown,

9 - additional clown,

10 - rocker arm,

11 - roller

12 - rod

13 - case,

14 - articulated support,

15 - adjusting screw-stop,

16 - fixing screw

17 - shaft

18 - bearing bearings

19 - recess,

20 - handle

21 - spring.

Figure 2 presents a diagram of the position of the lever-beam at different angles of rotation of the eccentrics, where m, n, p are the characteristic points of the profile of the eccentrics (mn is the area to overcome the resistance to elastic deformation, np is the area of plastic deformation), the position in figure 2 , and corresponds to the initial position of the handle, figure 2, b - turn the handle 30 °, figure 2, c - 75 °, figure 2, d - 90 °, figure 2, d - 125 °.

In Fig.3 shows a diagram of the interaction of the eccentrics with the roller, while Fig.3a corresponds to the interaction with the eccentric 8 in the section mn, and Fig.3b corresponds to the interaction with the eccentric 9 in the section np.

The manual bending device (Fig. 1) contains a base 1 with a cavity, on the inner surfaces of which a slide 2 is mounted on the guides. A holder 3 with a punch 4 is mounted on the slide. An emphasis 6 with a die 7 is mounted on the top cover 5. The eccentric mechanism is connected to the slide 2 and is made in the form of a pair of eccentrics: bearing 8 and additional 9, rocker arm 10 with roller 11 and rod 12 with housing 13.

The eccentrics are made with different eccentricities and different diameters, while the eccentric with a large diameter is made with a large eccentricity, the supporting eccentric 8 is made with less eccentricity and the hub and rigidly mounted on a shaft installed in the bearing bearings, an additional eccentric 9 is mounted on the hub of the carrier with the possibility of relative rotation with subsequent fixation, while the eccentrics are placed relative to each other so that the beginning of the working section of the additional eccentric coincides with the end of the slave what portion of the eccentric bearing during the rotation of the shaft. The rocker arm 10 is mounted on a hinge support 14 mounted on the base 1, the roller 11 is mounted on one end of the rocker arm in contact with the cam, the width of the roller is greater than the width of the working surface of any cam, and the second end of the rocker arm is pivotally connected to the housing 13. One end of the rod 12 is pivotally connected to the slider 2, and the other end is placed in the housing 13 and is installed in contact with the adjusting screw-stop 15 mounted on the wall of the housing, while in the housing there is a threaded hole in which to install n screw 16 for fixing the rod. The eccentric with the hub is rigidly mounted on the shaft 17 installed in the bearings 18, in the eccentrics, recesses 19 are made, the dimensions and shape of which are such that the recess in the eccentric mounted on the shaft is not blocked by the recess in the eccentric mounted on the hub. A handle 20 is rigidly fixed at the output end of the shaft, and a spring 21 is installed between the slider and the base.

The recess of the supporting eccentric can be made with a profile in the form of a segment of a broken line with rounded corners, and the recess of the additional eccentric can be made in the form of a cut along the chord.

Curves that limit the profiles of the notches can be of any shape that ensures the operability of the device. The profile of the recess of the supporting eccentric should be designed so that the roller interacts only with a section of the profile curve adjacent to the working section of the eccentric. The notch profile curve is limited by the point of intersection with the working section of the eccentric and the point of intersection with the profile of the eccentric in the perigee region — the point closest to the center of the eccentric. The profile of the recess of the additional eccentric must be such that the space bounded by the profile curve exceeds the area of the recess of the supporting eccentric and can cover the entire non-working part of the additional eccentric.

The intermittent movement of the tool acting on the material reduces the resistance of the material to deformation. As a result, the working surfaces of the eccentrics can be corrugated, which also helps to reduce the forces exerted by the operator during bending.

The device operates as follows. In the initial position, the roller 11 of the rocker arm 10 is located in the recess 19 of the eccentric 8 (Fig.2, a). With the beginning of the rotation and interaction of the eccentric 8 with the roller, the lever-arm deviates, and the roller rolls out onto the surface of the eccentric, contacting the latter at the point m (Fig. 2, b). In this case, the slider with the punch 4 moves to contact with the workpiece, based on the matrix 7. With further movement, the process of deformation of the workpiece begins with overcoming the force of elastic resistance of the metal. It requires maximum force. Due to the fact that the interaction of the roller with the eccentric 8 occurs in the area mn (Fig.2, b, c, d; Fig.3, a) close to the climax, the operator is not required to apply excessive force. The lower eccentricity of the eccentric 8 also helps to reduce the effort exerted by the operator. The position of the roller at point n corresponds to the onset of plastic deformation. With continued rotation of the handle, the roller at point n goes into interaction with the eccentric 9. In the np section (Fig. 2, g, d, Fig. 3, b), remote from the apogee (here there are relatively large displacements), plastic deformation and completion of the process are flexible ..

During the reverse rotation of the shaft with the eccentrics by means of the handle, the movable parts of the device return to their original position by means of a spring.

Changing the total length of the rod 12 and the housing 13 using screws is necessary to maintain the constancy of the parameters of the bending process. This is due to the fact that the dimensions of the dies and punches can vary over a wide range, and the surface area of the cover 5 of the base 1, on which the contact zones of the punch, the workpiece, and the die can be located, is quite long.

Thus, the device according to the invention allows to reduce the efforts exerted by the operator during bending, ensures the convenience of the operator and thereby increases his productivity, improves the quality of the manufactured knife, increases the service life of the device.

Information sources

1. Patent RU No. 2150343, B21D 5/02, 12/10/1999.

2. Patent RU No. 2212967, B21D 5/02, 04/05/2002 (prototype).

Claims (3)

1. A manual bending device comprising a base, a handle, an abutment with a die, a punch fixed in a holder connected to a slider, an eccentric mechanism connected to the slider, bearing bearings rigidly fixed to the base, a spring connected to the base, characterized in that the eccentric mechanism is made in the form of a pair of supporting and additional eccentrics, a rocker arm with a roller and a rod with a housing, while the eccentrics are made with different eccentricities and different diameters, and the eccentric is larger the diameter is made with a large eccentricity, the bearing eccentric is made with a smaller eccentricity and the hub and rigidly mounted on a shaft mounted in the bearings, the additional eccentric is mounted on the hub of the bearing eccentric with the possibility of relative rotation with subsequent fixation, while the eccentrics are placed relative to each other so that the beginning of the working section of the additional eccentric coincides with the end of the working section of the supporting eccentric in the direction of rotation of the shaft, recesses are made in the eccentrics, p the dimensions and shape of which exclude the overlapping of the recess of the supporting eccentric by the recess of the additional eccentric, the rocker arm is mounted on an articulated support fixed to the base, the roller is mounted on one end of the rocker arm in contact with the clowns, while the width of the roller is greater than the width of the working surface of any clown, the second the end of the rocker arm is pivotally connected to the housing, one end of the rod is pivotally connected to the slider, and the other end is placed in the housing and installed in contact with the adjusting screw-stop lennym on the wall of the housing, wherein the housing is in said threaded hole in which a screw for fixing the rod, a second end of the spring is mounted on the slider, and the handle is rigidly fixed on the shaft eccentrics. 2. The manual bending device according to claim 1, characterized in that the recess of the supporting eccentric is made with a profile in the form of a segment of a broken line with rounded corners, and the recess of the additional eccentric is made in the form of a cut along the chord. 3. The manual bending device according to claim 1, characterized in that the working surfaces of the eccentrics are grooved.

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