FR2533978A1 - TRANSMISSION AND GUIDANCE DEVICE COMBINING A JACK AND A TRANSMISSION ELEMENT - Google Patents

Abstract

1. A pressurized fluid-operated actuator comprising a lifting cylinder (2) the piston of which is movable inside a body (6), a piston rod (5), and at least one translating element (3) which is connected to the free end (5a) of the piston rod (5) through a strap (4) and is disposed in parallel to the lifting cylinder and is movable in a guide track (7) provided on the outside of the body (6), characterised in that the outer portion of the body (6) has polygonal cross-section along the entire length thereof, and that each outer surface of the body (6) is formed with a longitudinally extending slot (7), a respective one of said longitudinal slots (7) being used as guide track for a translating element (3) while the free longitudinal slots are provided for mounting the actuator on the mechanical unit (12) or another support.

Description

"Transmission and guidance device combining a cylinder and an element

  The present invention relates to a transmission device

  and guide combining a cylinder and a transmission element.

  Devices of this type are known which consist in coupling the transmission element, such as a rack, in the extension of

  the cylinder rod Such a device has many drawbacks.

  and, in particular, to be of a considerable bulk and to include end to end two elements, jack and transmission element, which has the effect of causing beyond a certain value of stroke of the jack a buckling of l 'transmission element It is therefore necessary to provide means for guiding the transmission element and this guiding must necessarily take place in the environment where it moves. The invention aims to remedy these drawbacks by providing

  a device which, while giving full satisfaction in terms of function-

  is considerably reduced in size compared to

to known devices.

  To this end, in the device which it concerns, on the one hand,

  the body of the hydraulic or pneumatic cylinder present, on its face ex-

  dull, at least one longitudinal groove capable of constituting, at least partially-

  Lely, a slide and, on the other hand, at least one transmission element such as a rack, coupled to the rod of the jack, is slidably mounted.

  parallel to this rod in the aforementioned slide.

  The size of this device is considerably less

  than that of known devices of the same type and whose transfer element

mission has the same race.

  According to a preferred embodiment of the invention, the external lateral surface of the cylinder body is of polygonal cross section and each facet has a longitudinal groove capable of serving

  slide to a transmission element and contribute to its position-

  and its attachment to the mechanical assembly for which it is intended

or on any other medium.

  Preferably, each longitudinal groove in the body of the jack which must constitute a slide is partially closed by bars fixed along each of its edges and forming two longitudinal lips.

  of the transmission element.

  In the case where the cylinder is of the through rod type, an element

  transmission can be coupled to each end of said rod.

  The cylinder can also be of the double working piston type.

opposites.

  When this device is used to transform a rectilinear translational movement into rotation, according to a simple embodiment of the invention, the transmission element is a rack and pinion

with a pinion.

  It should be noted that by providing the inlet and outlet ports for the pressurized fluid supplying the actuator on one of the facets of the latter's body, by the judicious choice of the longitudinal groove or grooves which should serve as a slideway for the transmission element it is possible

  to orient in the desired direction the aforementioned orifices.

  In any case, the invention will be well understood using the

  description which follows with reference to the appended schematic drawing representing

  as many non-limiting examples of embodiments of this device: FIG. 1 is a view in longitudinal section along 1/1 of FIG. 2, illustrating a first embodiment of this device; Figure 2 is a cross-sectional view along 2/2 of Figure 1; Figures 3 and 4 are views similar to Figure 1 and Figure 2 respectively, illustrating an alternative embodiment of this device;

  Figures 5 and 6 are views similar to Figures 1 and 3, illus-

  trant two other alternative embodiments of this device; Figure 7 illustrates the mode of use of a device of a known type and

  Figure 8 is a view similar to Figure 7 in the case of use

tion of the device of the invention.

  As the drawing shows, this device essentially comprises-

  a cylinder (2) and a transmission element which, in this example, consists of a rack (3), coupled with a flange (4) to

  the outgoing end (5 a) of the rod (5) of the jack.

  As shown in particular in Figure 2, the body (6) of the cylinder (2) has a cross section of substantially square outer profile and has on each of its four facets a longitudinal groove (7)

  suitable for being used to form a slide for guiding the rack

1 st (3).

  In the example illustrated in Figures 1 and 2, there is provided a single rack (3) and as shown more particularly in Figure 2, the groove (7), located on the left in this figure, and intended to serve as a slide to the rack (3), is partially closed by two bars (8) fixed along the edges of the groove (7) using screws (9) and

  so as to form along this groove (7) retaining lips, delimited

  both a T-section slide capable of ensuring the retention of the

  slide (3) of complementary section.

  As shown in Figure 1, the inlet and outlet ports (11 Y of the pressurized fluid intended to supply the cylinder (2) are arranged on the same facet of the body (6) This arrangement, combined with the

  presence of the four longitudinal grooves (7), allows the user to orient-

  ter at will the holes (11) since it can choose one of the four grooves (7) to form the slide of the rack (3), this choice being made

  obviously depending on the mode of use of the device.

  As can be seen, the rack (3) and the rod (5) of the jack (2) are not placed end to end but parallel to one another and the means for guiding the rack (3) are arranged directly

  on the body (6) of the jack (2) Consequently, this device is

  sharply reduced compared to devices of this type but, moreover, it has a very lower cost price since the body (6) of the jack

  (2) largely participates in guiding the rack (3).

  The example illustrated in Figures 3 and 4 differs from that of Figures 1 and 2 in that two racks (3) are coupled to the same end of the rod (5) of the jack (2) by a double flange (4 a), the grooves (7) chosen to serve as their slides being those found

  on the two opposite facets of the body (6) of the jack (2) -

  In the example illustrated in FIG. 5, the jack (2a) is of the through rod (5a) type and each of the two racks (3) guided in slides arranged in the grooves (7) on two opposite faces of the body (6) is coupled by a flange (4) to one end of the rod

(5 a).

  In the example illustrated in FIG. 6, the jack (2b) is of the type with two independent piston rods (5b) and with opposite operations,

  each rod (5 b) being coupled by a flange (4) to one of the two cremail-

  leers (3) whose movements are reversed.

  Figures 7 and 8 tend to highlight the reduction in bulk.

  somewhat specific to the device of the invention.

  FIG. 7 shows a device of known type in which the rack (3) is assembled end to end to the rod (5) of the jack (2) whose body (6) is fixed to the mechanical assembly (12), to which the device is intended, using a flange (13) fixed to the body (6) and spacers (14) connecting the flange (13) to the mechanical assembly (12) Naturally, the length of the spacers ( 14) is determined by the length of the stroke of the rod (5) of the jack (2) and therefore of the rack (3), and the greater this stroke, the greater the cross section of the spacers (14)

must be important.

  In the example illustrated in FIGS. 7 and 8, the mechanical assembly

  that (12) is an industrial mold in which pinions (12 a) must be rotated from the linear movement of the rod

(5) of the cylinder (2).

  FIG. 8 shows the adaptation of the device of the invention to the same mechanical assembly (12), the device of the invention used in

  this example being identical to that illustrated in FIGS. 1 and 2.

  The comparative examination of FIGS. 7 and 8 clearly shows the reduction in size resulting from the use of the device of the invention as well as the reduction in its cost price as a result of

  the removal of important mechanical elements.

  It should also be noted that the polygonal shape of the external surface of the body (6) of the jack (2) facilitates its correct positioning relative to the mechanical assembly (12) or any other support, the groove

  (7) corresponding to its bearing face which can also participate in obtaining

tion of this correct positioning.

  It should also be noted that, in this device as in any other device of the same type, it is possible to provide means for detecting the position of the cylinder rod, end-of-stroke detection means, means for regulating gear and any other accessories

of this order.

  As is obvious and as is clear from the above, the invention is not limited to the sole embodiments of this device described above by way of examples; on the contrary, it embraces

  all variants.

Claims (2)

CLAIMS - I. Transmission and guide device combining a cylinder and a transmission element, characterized in that, on the one hand, the body (6) of the hydraulic or pneumatic cylinder (2) has, on its external face, at at least one longitudinal groove (7) capable of constituting, at least partially, a slideway and, on the other hand, at least one transmission element (3), such as a rack, coupled to the rod (5) of the jack ( 2) and slidably mounted parallel to this rod (5) in the aforementioned slide.   2. Device according to claim 1, characterized in that   the external lateral surface of the body (6) of the jack (2) is of cross-section   dirty polygonal and each facet has a longitudinal groove (7) capable of serving as a slide for a transmission element (3) or   to contribute to its positioning and its attachment to the mechanical assembly   that (12) for which it is intended or on any other medium.   3 Device according to claim 1 or claim 2, characterized in that each longitudinal groove (7) of the body (6) of the jack   (2) before constituting a slide is partially closed by barrets-   tes (8) fixed along its edges so as to form two longitu-   retention elements of the transmission element (3).   4 Device according to any one of the preceding claims.   tes, characterized in that, in the case where the jack (2 a) is of the through rod type (5 a), a transmission element (3) is coupled to each of the ends of the rod (5 a).   Device according to any one of Claims 1 to 3,   characterized in that the jack (2b) is of the double piston type of function-   opposite elements, one element being coupled to the outgoing end of each rod (5b) of a piston.   6. Device according to any one of the preceding claims.   tes, characterized in that, in the case where it is intended to transmit   a rectilinear translational movement in rotation, the transmission element   sion (3) is constituted by a rack engaged with a pinion (12 a).