FR2480386A1 - ARTICULATED SYSTEM AT BRIEF SLOWING AT MID-STROKE - Google Patents

Abstract

THE PRESENT INVENTION CONCERNS A CYCLOIDAL DRIVE SYSTEM WHICH IS SLOWED DOWN AT MID-STROKE, AND WHICH IS INTENDED FOR PRESSES AND ELEVATOR DEVICES, IN PARTICULAR SINGLE TYPES OF HYDRAULIC PRESSES CONTROLLED FROM THE BOTTOM TO AUTOMATIC MECHANISMS. THE SYSTEM INCLUDES A FIXED GEAR 16, A CRANK 17, 18 THAT CAN OSCILLATE ON THE AXIS 14 OF THE FIXED GEAR AND CARRYING AN ECCENTRIC GEAR 21 IN TAKEN WITH THE FIXED GEAR, AN ECCENTRIC 22 FIXED TO THE SHAFT 19 OF L 'ECCENTRIC GEAR AND AN ELEVATOR ARM 23 ON THE ECCENTRIC CONNECTED TO THE DRIVEN ORGAN.

Description

1.

  The present invention relates to communication systems.

  cycloidal signals whose speed is reduced at mid-stroke so as to minimize shock and reduce the noise level of the parts moving in a reciprocating movement, for example, when the parts are lifted or conveyed. American patent application No. 51,677 of June 25, 1979 in the name of the applicant, having as title:

"Cycloidal Drive" describes an arrangement that can be used

  dried in some soldering presses and the like. The disposi-

  tif which is the subject of this patent application does not have 1O certain characteristics unlike the present invention, which can thus be the subject of applications

  in other types of presses and lifting devices.

  The following prior art patents are related

  considered to be within the scope of the present invention, but do not include the characteristics and advantages making

the subject of these claims:

  Gervais patent n 3,559,767 Matsushita patent n 3,971,261 Seki patent n 3,956,942 Staecker and other patent n 2,822,696 Fracke patent n 3,468. 173 Koderman patent no.3,886,805 2. Hosoda and other patent no 3,921,465 Mori and other patent no 3,960,024 Obra patent no 4,020,708 Obra patent no 4,089,228 Drungil patent no 4,095,522 An object of the present invention is to forecast

  an articulated system of the cycloidal type with short stop at mid

stroke which is particularly applicable to hydraulic presses

simple type of controls operated from below as well as lifting mechanisms for type C vice structures and

automated parts conveyors controlled by cylinders.

Another object of the present invention is to provide an improved system of this type, which is simple,

  reliable and economical construction.

  Other objects, features and benefits of

the present invention will be found in the description and

in the following claims as well as in the drawings

support.

  The articulated system with short stop of movement at mid

  stroke of the present invention comprises a fixed gear,

a motor shaft capable of oscillating on the axis of the fixed gear

  xed, a crank fixed to the shaft, an eccentric gear rotatably mounted at the outer end of the crank and in engagement with the fixed gear, an eccentric fixed to

the axis of the eccentric gear and which can rotate on it

  ci, and a lifting arm having an inner end

rotatably mounted on the eccentric and one outer end

  lower comprising a means of connection to a driven member.

  The present invention will be well understood during the

  following description made in conjunction with the drawings below

  joints in which: FIG. 1 is a perspective view of the articulated system according to the present invention; Figure 2 is a schematic view showing the position of the parts when the lifting arm is in

its lowest position; -

  Figures 3 to 8 are figures similar to 3. Figure 2, which show the movement of the parts when the lifting arm comes to its highest position, as well as the geometric location of the axis of the eccentric;

  Figure 9 is a diagram showing the variation

tion of the elevation stroke as a function of time for a constant speed of the motor shaft;

  Figure 10 is a perspective view shown

  both an application of the present invention to the control from below of a hydraulic press;

Figure 11 is a perspective view shown

  both an application of the present invention as a lifting device for a C-shaped vice structure; and

  Figure 12 is a perspective view shown

both an application of the present invention as a mechanism

  elevator of an automated parts conveyor.

The articulated system of the present invention is generally represented at 11 in FIG. 1 and comprises a pair of ordinary bearings 12 and 13 distant from each other. A shaft 14 extends between the bearings in which it is mounted and supports a coupling means 15 located outside of the bearing 13 intended to be connected to an energy source. A fixed gear 16, in the form of a gear

  sun, is fixed towards the inside of the bearing 12 and is concentrated

  stick on the shaft 14. Two cranks 17 and 18 are fixed by-

  parallel to each other to the shaft 14 between the gear 16 and the bearing 13. A shaft 19 of eccentric gear is rotatably mounted at the outer end of the cranks 17

and 18. This tree extends between the cranks and, outside

  laughing of these, in the direction of the bearing 12.

An eccentric gear 21 is fixed to the part of

the shaft 19 extending outwards. This gearing exceeds

  stick is engaged with the gear 16. The pitch circle of the gear 16 is shown as having a diameter

double that of gear 21.

  An eccentric 22 is fixed to the shaft 19 and placed between the cranks 17 and 18. A lifting arm, shown 4.

  at 23, has an inner end 24 rotatably mounted

  tion on the eccentric 22 and an outer end 25 pre-

view to be connected to a driven member. The middle part

  26 of arm 23 is curved so that during the movement

  ment of the lifting arm between its extreme positions, the arm

  has a space 27 which will avoid its contact with the

tie 28 of the cranks of the shaft 14 which connects the arms 17 and 18. The operation of the assembly 11 is shown in Figures 2 to 8. Starting from a position shown in Figure 2 o the outer part 25 of the arm 23 is in its lowest position, the center 29 of the eccentric 22 is in the position shown. Part 25 of

arm 23, which is caused to move along the vertica-

  31, is therefore in its lowest position. We no-

tera that the space 27 formed by the curvature of the arm 23 and

  more particularly by part 26, will allow the arm to be

  avoid the part 28 of the cranks which is fitted

on the shaft 14 and connects the arms 17 and 18.

During a rotation of 300 of the shaft 14 and

cranks 17 and 18, shown in Figure 3, the planar action

  shutting down gears will cause the eccentric to rotate

  22 with an additional angle of 600. This will result in a

  upward placement of the part 25 of the arm 23. When the cranks are again rotated by an angle of 300 (position corresponding to 60, FIG. 4), the eccentric 22 will have rotated by an angle of 1200. L elevation of the part 25 of the crank arm 23 will be faster than before. When the arms of

  crank 17 and 18 reach their position at 900, represented by

felt in figure 5, the eccentric 22 will have rotated 1800. The speed of elevation between figure 4 and figure 5 will be

slower than before, because the center 29 of the eccentric moves

  will actually place downwards relative to the axis of the shaft 19. The cranks 17 and 18 moving again from

300 to take the position of FIG. 6, the end ex-

  25 of arm 23 will move again at speed 5.

  slower since the center 29 of the eccentric con-

  keeps moving downward relative to the axis of the

  bre 19. Moving to the position shown in Figure 7, at a new angle of 30 for the cranks 17 and 18, will cause the center 29 to move towards

  the top with respect to the axis of the shaft 19. Thus, the extremi-

  outer tee 25 of arm 23 will rise at a relative speed-

  fast. When the position shown in Figure 8 is

  reached, cranks 17 and 18 will be in the posi-

  tion and the same will apply to the outer end 25 of the arm 23. However, the speed of movement

  will be somewhat slower than during the last increment.

  When it is desired to return the arm 23 to its lowest position, the shaft 14 will be rotated in the opposite direction by means of the coupling means 15. The

  lifting arm will follow the same path as before, slowed down

  halfway through, and will arrive at the position shown in

figure 2.

Figure 9 is a diagram showing the variation

  tion of the elevation stroke between Figure 2 and Figure 8, that is to say between the lowest position and the highest position of the cranks 17 and 18. This diagram also applies when operating in the opposite direction. For a constant speed of rotation of the shaft 14, the part

  start of the ascent race, represented at 32, will be

  laterally fast. At mid-race, represented at 33, there will be a slowdown or period of brief momentary stop, and the

part 34 of the position line indicates the resumption of the

  relatively fast upwards. In a construction

typical, if the displacement speed at 34 is X mm per se-

  count, represented by circle 35, the speed of movement

  at part 33 will be approximately X / 7 mm per second.

  With the arrangement shown, the member driven in the area represented by the circle 37 will be located at approximately

  46% of the total elevation stroke measured from the bottom.

It will be understood that other arrangements are possible depending on

the present invention.

  6. The path from center 29 to eccentric 22 is

  represented by line 36 of figure 8. This geometrical place

  stick is obtained by combining the displacements of the crank arms with the planetary movement of the gear 21 around the gear 16. Figure 10 shows the articulated system 11 applied to a press. The press, represented at 38, is a hydraulic press of a simple type with control from below comprising a base 39, pillars 41 and a plate 42 which is raised and lowered by the mechanism 11. As shown, two mechanisms They are arranged side by side at the right end 43 of the plate 42, and are driven by a common shaft 44 placed between them. A second pair of

  mechanisms 11 (not shown) is placed at the left end

  che of the plate 42 and is driven in synchronism with the two mechanisms shown. Open parts 45 are provided in the base 39. The outer ends 25 of the lifting arms 23 have openings shown

in 46.

  In the operation of the embodiment of the

figure l0, the plate 42 will be raised and lowered by the

  nisms 11. At approximately halfway between each lift or lower stroke, the table will be slowed down as

described in conjunction with Figure 9.

  FIG. 11 represents another installation of the mechanism 11, this time in a device for lifting a vice

  in C. The console is generally represented in 48 and com-

  carries a base 49 surmounted by a plate 51. Four mecha-

  nisms 11 are arranged inside the base 49 and function

  will operate in a manner similar to that described in liai-

its with figure 10.,

  Figure 12 shows a third type of installation.

  lation, i.e. a lifting mechanism for conveyor

  automated parts actuated by cylinder. The unit is generally

  shown in 52 and includes a base 53 above

  which are arranged two bars 54 of conveyor

  reciprocating and driven by cylinder in parallel 7.

  to each other. These bars carry legs 55 of trans-

  fert of parts (not shown). A table 56 is provided which is narrower than the space separating the bars 54, this table comprising tabs 57 for positioning the parts. Four mechanisms 11 are placed at the four corners of the table 56 and are connected to the latter by supports 58. During the operation of the mechanisms 11, the table

56 will move between a lower position located above

below the level of the bars 54 and a higher position, re-

  presented in figure II located above the bars. The agen-

  cement is such that the slowing down of table 56

  must immediately before the engagement of the piece, during the upward stroke, and immediately before it

falls on the bars 54 during the race to the bottom.

  The appreciation of some of the measurement values

  above should take into account that they pro-

  come from the conversion of Anglo-Saxon units into metric units.

  The present invention is not limited to the examples

  ples of realization which have just been described, it is on the contrary susceptible of variants and modifications which

will appear to those skilled in the art.

8.

Claims (7)

  1 - Articulated system with short stop at mid-stroke,   characterized in that it comprises a fixed gear, an ar- bre motor oscillating on the axis of the fixed gear, a ma-   level fixed to the shaft, an eccentric gear rotatably mounted at the outer end of the crank and in engagement with the fixed gear, an eccentric fixed to the axis of the eccentric gear and able to rotate with it, and a lifting arm having an inner end mounted in   rotation on the eccentric and an outer end carrying a connecting means to a driven member.   2 - System according to claim 1, characterized in that the fixed gear comprises a sun gear.   3 - System according to one of claims 1 or 2,   characterized in that it further comprises a second mani-   velle attached to the shaft and parallel to the first crank,   the eccentric being placed between the cranks, the fixed age being placed outside the cranks.   4 - System according to any one of the claims   tions 1 or 2, characterized in that it further comprises ordinary bearings supporting the opposite ends of the shaft, the fixed gear and the cranks-being arranged between these bearings. 0 - System according to one of claims 1 or 2,   characterized in that the lifting arm has a curved construction, as a result of which it will not come into contact with the tree during its rotation.   6 - System according to one of claims 1 or 2,   characterized in that the diameter of the pitch circle of the   fixed peening is twice that of the eccentric gear than.   7 - System according to one of claims 1 or 2,   characterized in that it further comprises a second articulated system constructed like the previous one, the drive shafts of the two systems being coaxial, and a common shaft being placed between the drive shafts and coupled to them for cause his training.   9. 8 - System according to claim 7, characterized in that the driven member comprises a lifting plate, the two articulated systems being connected to one end of the   tray, and a second pair of articulated systems zymétri-   only opposite to the first pair being connected to the other end of the tray. 9 - Articulated system with short stop at mid-stroke, characterized in that it includes a pair of computer bearings   naries, an oscillating shaft supported by the bearings and extending between them, a motor coupling means on the shaft, a fixed sun gear concentric with the shaft to   inside one of the bearings, a pair of cranks pa-   parallel and distant from each other fixed to the shaft between   the fixed gear and the other bearing, a gear shaft ex-   centric rotatably mounted at the outer ends of   cranks, an eccentric gear having a significant diameter   considerably lower than that of the sun gear fixed to the shaft of the eccentric gear and in engagement with the sun gear,   an eccentric attached to the shaft of the eccentric gear in-   be the cranks, a lifting arm having one end inner rotationally mounted on the eccentric, the arm viewer having a curved shape between its interior ends   superior and exterior, as a result of which the lifting arm   avoid the motor shaft during its movement between its positions   tions, and a driven member attached to the ex- of the lifting arm.