FR2492693A1 - LOADING AND / OR UNLOADING DEVICE FOR PRESSES, PUNCHERS OR SIMILAR MACHINE TOOLS - Google Patents

Abstract

THIS LOADING AND / OR UNLOADING DEVICE FOR PRESSES, PUNCHING MACHINES OR SIMILAR MACHINE-TOOLS INCLUDES A TRANSPORT ARM FORMING PART OF A PARALLELOGRAM LINKAGE WHICH IS CONNECTED BY ITS LEVER OPPOSED TO THE TRANSPORT ARM BY TWO AUTALUX OF FIXED ROTATIONS, ONE OF WHICH IS MOUNTED LIKE A CRANK ON A DRIVE SHAFT. THE DRIVE SHAFT 1 OF THE FIRST CRANK 2 CAN BE DRIVEN BY MEANS OF A SERVO MOTOR 3, AND IN THAT THE LEVER OF THE PARALLELOGRAM LINKAGE WHICH ATTACKS THE OTHER END 2A OF THE FIRST CRANK 2 IS REALIZED UNDER FORM OF AN ADDITIONAL SECOND CRANK 4 OF WHICH THE DRIVE SHAFT 6, PASSING THROUGH THE FIRST CRANK 2, CAN BE DRIVEN BY MEANS OF ANOTHER SERVO MOTOR 7.

Description

The invention relates to a loading and / or unloading device

  for presses, punching machines or similar machine tools, with a transport arm which performs a practically rectilinear horizontal reciprocating movement which is followed in its terminal parts by vertical movements,

  the transport arm being part of a parallel linkage

  the gramogram which is connected, by its lever opposite the transport arm, to two parallel levers mounted around fixed centers of rotation, levers one of which is mounted in the manner

  a first crank on a drive shaft.

  For loading and removing parts in presses, the loading and unloading devices have been proposed.

  most diverse unloading. To guarantee an improper removal

  cable parts, which often have a relatively large overall height, from the Lravail area

  press without risk of damage, it is often necessary

  make sure that the corresponding transport arms cover everything

  first a vertical path, then a longer horizontal path.

  This combination of movements then follows, in most cases, a new vertical movement downwards to

  deposit the coin. When loading the press, this success

  The movement takes place in the corresponding reverse order.

  A model that substantially meets this requirement is

  described in German patent application 24 39 722. This provision

  known disadvantage, however, has the disadvantage that the course of movements is kept within relatively limited

  narrow, that in addition a control device is provided

  relatively complicated by means of switches for the corresponding control rollers and that, in addition, a modification of the course of movements planned at the start makes necessary major and complicated transformations, that is to say costly. To obtain by simple means the various desired movements of the transport arm, each offset by 90 relative to each other, including the transition curves between the horizontal movement and the vertical movement, it has been proposed elsewhere, in the German patent application

  28 47 543, a suitable device for loading and / or unloading

  loading in which the transport arm is articulated on an in-parallelogram linkage which for its part has two parallel arms pivoting around fixed centers of rotation, one arm of which is produced in the manner of a crank as a shaft control, and there is provided, for obtaining a determined course of movements, a cam control whose cam is fixed on the control shaft and cooperates with

  guide rollers of a sliding element which carries at its extremi-

  upper tee a guide mounted for rotation, through which passes the extension of a parallelogram lever which is guided therein

sliding.

  With this embodiment, the trajectory of the transport arm was precisely predetermined and practically

  immutable. Only the length of the path at elevation and at-

  lowering could be changed in this case.

  On the other hand, the object of the present invention is to allow the trajectory of the transport arm to be fixed at will, in particular in the extreme parts of the course of its movements and, for example, to remove a part with the clamp and even, in if necessary, to allow, after lowering the transport arm, to move it horizontally on

a short distance again.

  To achieve this goal, it is proposed according to the invention,

  in a loading and / or unloading device for

  ses, punching machines or similar machine tools, with a transport arm which performs a practically rectilinear horizontal reciprocating movement which is followed by vertical movements in its terminal parts, the transport arm forming part of a linkage in a parallelogram which is connected, by its lever opposite the transport arm, to two parallel levers mounted around fixed centers of rotation, levers one of which is mounted in the manner of a first crank on the control shaft, characterized in that the drive shaft of the first crank can be driven by means of a servomotor, and in that the lever of the parallelogram linkage which attacks the other end of the first

  crank is produced as a second additional crank

  with the control shaft passing through the first

  crank, can be driven by another servo motor.

  A particular embodiment of this device

  is characterized in that the drive of the second crank

  it is carried out by a toothed segment freely mounted on the control shaft the first crank, segment which is on the one hand

  in engagement with a toothed wheel which is fixed on an inter-

  medium driven by the servo motor and which is on the other hand engaged with a toothed wheel which is mounted without possibility of rotation on the second crank and which acts on its side on

  a second toothed segment which is fixedly mounted on the drive shaft

second crank.

  Furthermore, it is advantageous, in a manner known per se, for the transmission ratio of the first toothed segment to the center of rotation of the first crank, relative to the

  second toothed segment at the center of rotation of the second mani-

  be 1: 2. It is also proposed that the two

  cranks is of the same length, in a manner known per se.

  By the embodiment according to the invention, the transport arm can carry out, by the two intersecting movements, a path such that the part can be transported in a manner adapted to the particular needs, precisely

  in the extreme parts of the transport path.

  The invention is explained below in more detail.

  lée using drawings which represent, in part schematic-

  ment, any exemplary embodiment.

  Figure 1 is a vertical sectional view of the device

  according to the invention in its middle position.

  Figures 2 and 3 are previous views of the device.

  tif in its two extreme positions.

  In the embodiment shown, the device according to the invention is fixed on a support 19 which is mounted

  in front of the press shown schematically at 20. The upper tool

  laughter of the press is designated by 21 and its lower tool by 22. The transport arm 13 proper of the device

  intended for loading and unloading includes, for example-

  ple for the transport of parts 5 with large surface area, such as

  body panels, crossbars 14 and 15 to which

  the suction cups 16 are fixed which cooperate with the part 5.

  The transport arm 13 constitutes with the levers 4, 17 and 18 a parallelogram linkage. At the upper mounting points of the levers 4 and 17 are articulated two other levers 2 and 23 which are mounted around fixed centers of rotation 24 and 1, the center of rotation 1 being produced in the form of a control shaft. With the control shaft 1, the lever 2 constitutes a first crank whose drive is obtained by means of a servomotor 3. At the end 2a of the first crank 2 is mounted a control shaft 6 which forms , with the lever 4, a second crank, the control shaft 6 being driven by

another servo motor 7.

  On the control shaft 1 is fixed a first segment

  toothed 8 which cooperates, on the one hand, with a toothed wheel9 of the ar-

  intermediate bre 10 of the servo-motor 7, and which is, on the other hand, engaged with an intermediate wheel 11 which is fixed on an axle 25 rotatably mounted in the first crank 2, and which is, in turn, in taken with a second toothed segment 12 which is fixed to the control shaft 6 of the second crank 4. By the two movements of levers produced by the servomotors 3 and 7, the transport arm 13 can perform any desired movements at the ends of its stroke, as can be

  see Figures 2 and 3. In Figure 2, the transfer arm

  port 13 has entered the press tool area and after gripping the part 5, it will transport it to the position

  represented on the left in points and dashes, position which appears

  rait in solid lines in Figure 3. We have indicated in points and dashes and designated by I, II and III three possibilities

  different for the transport route.

6.

Claims (4)

CLAIMS _______ ______   1. Loading and / or unloading device for presses, punching machines or similar machine tools, with a transport arm which performs a practically rectilinear horizontal back-and-forth movement followed by vertical movements in its terminal parts , the transport arm forming part of a parallelogram linkage which is connected, by its lever opposite the transport arm, to two parallel levers mounted around fixed centers of rotation,   levers, one of which is mounted in the manner of a first crank   the on a control shaft, characterized in that the control shaft (1) of the first crank (2) can be driven by means of a servomotor (3), and in that the lever of the linkage in parallelogram which attacks the other end (2a) of the first crank (2) is produced in the form of a second   additional crank (4) including the control shaft (6), not   health through the first crank (2), can be driven   by means of another servo motor (7).   2. Loading and / or unloading device according to claim 1, characterized in that the drive of the second crank (5) is obtained by means of a toothed segment (8) freely mounted on the control shaft ( 1) of the first crank (2), segment which is, on the one hand, engaged with a toothed wheel (9) fixed on an intermediate shaft (10) driven by the servo-motor (7), and which is, on the other hand, in engagement with a toothed wheel (11) which is mounted without possibility of rotation on the second crank (5) and which acts on its side on a second toothed segment (12) which is fixedly mounted on the shaft   control (6) of the second crank (4).   3. Loading and / or unloading device according to   any one of claims 1 or 2, characterized in   that the transmission ratio of the first toothed segment (8) to the center of rotation of the first crank (2), relative to the second toothed segment (12) to the center of rotation of the second crank is 1: 2.   4. Loading and / or unloading device according to   - any one of claims 1 to 3, characterized in that   that the two cranks (2 and 4) have the same length, in a manner known per se.