FR2730180A1 - IMPROVEMENT FOR A TIGHTENING DEVICE OF THE TYPE INCLUDING A PISTON-OPERATED LEVER - Google Patents

Abstract

Clamping device (1) intended to hold a construction part to be machined or welded, device of the type comprising a lever (2) pivotally mounted in a yoke (100) of a device body (4) to be actuated in pivoting by the movement of a piston, between a first position called inactive release position, and a second position called active retaining position, said lever being connected to the piston by means of control and connection means comprising a sliding part ( 17) integral in movement with the piston, and which is connected to the lever by means of at least one connecting rod (18a, 18b), characterized in that the lever (2) comprises a fitting and pivoting part (19) which entirely occupies the slot in the yoke (100).

Description

IMPROVEMENT FOR TYPE TIGHTENING DEVICE

  INCLUDING A PISTON-DRIVEN LEVER

  The present invention relates to a clamping device comprising a lever actuated hydraulically or pneumatically by a piston of the type used to hold workpieces

or solder.

  In the industrial field, it is necessary to retain the parts so that, for example, they can be machined or assembled by welding. It is, of course, used different devices such as, for example, clamps or systems of latches, manually operated, which have a number of drawbacks. Also, manufacturers have developed automatic tightening systems, pneumatically or hydraulically controlled, which comprise at least one lever, actuated from an inactive position to an active clamping position and vice versa, by the displacement of a piston caused pneumatically or hydraulically. We know, for example, those described in French patent applications published under the numbers 2 183 689, 2 510 932 and 2 536 323. In all these known embodiments, the pivoting lever is retained in a yoke open at least towards the front and upwards, revealing the control and connection members which move there, and in particular the connecting rods as well as the sliding control part. As a result, the chips or weld projections due to the operations carried out on the retained parts can penetrate into the yoke, creating dirt preventing the movement of the moving parts. This has a significant drawback which makes current devices unsatisfactory, or even unusable in

certain cases.

  The present invention therefore seeks to remedy the drawbacks of current devices by proposing a new concept of a particularly reliable and simple device, offering a seal against various soils. Thus, the clamping device intended to retain a construction part to be machined or welded, according to the invention is of the type comprising a lever pivotally mounted in a yoke of a device body to be pivotally actuated by the movement of a piston between a first position known as the inactive release position, and a second position known as the active retaining position, said lever being connected to the piston by means of control and connection means comprising a sliding piece integral with movement with the piston, and which is connected to the lever by means of at least one connecting rod, and is characterized in that the lever comprises an embedding part

  and pivoting which fully occupies the clevis slot.

  According to an additional characteristic, the control and connection means comprise two connecting rods which are provided in recessed housings produced in the internal faces of the two side walls of the yoke, said housings not opening out.

not outside.

  According to another characteristic, the sliding control part is disposed sliding in the middle part of the device body, and has the general shape of a U, consisting of an end wall and two vertical side walls whose ends bear the axis with its two rollers or bearings which are guided in vertical displacement in respective blind lights, lights which do not

not open outwards.

  Other characteristics and advantages of the invention will emerge

  of the description which will follow with regard to the appended drawings which are not

  given only by way of nonlimiting examples.

  Figures 1 to 3 are exterior views showing the device

in its active clamping position.

Figure 1 is a side view.

  FIG. 2 is a view along F1 of FIG. 1.

Figure 3 is a top view.

  Figures 4 to 6 are exterior views showing the device

  in its inactive release position.

Figure 4 is a side view.

  FIG. 5 is a view along F1 of FIG. 1.

  Figure 6 is a top view. Figure 7 is a longitudinal sectional view along VII-VII of the

Figure 3 and Figure 8.

  FIG. 8 is a sectional view along VIII-VIII of FIG. 7.

  Figures 9 and 10 are partial sectional views along

  respectively IX-IX and X-X of figure 12.

  Figures 11 and 12 show the device body alone.

Figure 11 is a rear view.

  Figure 12 is a longitudinal sectional view along XII-XII.

  Figures 13 and 14 are illustrations showing more particularly the control and connection means, in the active clamping position (Figure 13) and in the inactive release position

  (Figure 14), the retaining wall of the foreground having been removed.

  Figure 15 is an exploded perspective with partial cutaway.

  The retaining device (1) of the invention comprises a retaining lever bearing the general reference (2) pivotally mounted about an axis (3) on a device body (4), allowing said lever to be movable between two positions, a first position (A) called the inactive position for releasing the part to be welded or machined (5), and a second position (B) called the active retaining position. The retaining lever (2) is actuated by the displacement of a piston (6) moving in a chamber (7) made in the lower part (8) of the body. Note that the upper part (9) of said body has the general shape of a yoke (100) which is formed by two parallel walls (10a, 10b) creating between them a slot (11) intended for the passage of the lever (2), and that said two parallel walls (10a, 10b) are also pierced with a transverse hole (12)

  X-X axis, in which is engaged the pivot axis (3) of the lever (2).

  The piston (6) is advantageously cylindrical and the chamber (7) of complementary shape comprises a lower end wall (13) and an upper wall (14) pierced with a hole (15) intended for the passage of the piston rod (16) at the end of which is fixed a sliding piece (17). Add to this that the latter is connected to the retaining lever (2) by means of two lateral connecting rods (18a, 18b), which constitute, with the sliding part (17), the control and connection means for the lever (2). Of course, the chamber (7) comprises two holes (70, 71) for the arrival and departure of fluid or air

  necessary to move the piston.

  Note that the retaining lever (2) is formed by an embedding part (19) constituting the actuating and pivoting part of the lever (2). Add to this that, according to a characteristic of the invention, the embedding and pivoting part (19) has the shape of a cylinder of radius (r) centered on the axis (XX ') and of thickness ( e), extended by an arm (20) constituting the active retaining part of said lever (2). The embedding part (19) is arranged between the two side walls (0la, 10b) to pivot around the axis (XX ') and thus be retained laterally. For this purpose, the thickness (e) of the embedding part is substantially equal to or less than the clearance near the width (l) of the slot (11), that is to say the distance between the internal faces.

  (21a, 21b) of the two respective walls (10a, 10b).

  The two links (18a, 18b) are arranged against and on either side of the transverse faces (22a, 22b) of the embedding part of the lever. Each of the links is such that one of its ends is articulated on the embedding and pivoting part (19) of the lever (2) by means of an axis (27) engaged in a corresponding hole (270), while the Another of its ends is articulated at the end of the sliding part (17) thanks to a transverse axis (26). Note that the latter (26) passes freely through the embedding and pivoting part of the lever, thanks to a clearance hole (28) whose dimensions are such that the axis (26) of move around freely. Furthermore, recesses are provided (23a, 23b) made in the side walls

  to allow these rods to be housed there and to be able to place themselves there.

  Also, the recessed housings (23a, 23b) are produced more precisely in the facing internal faces (21a, 21b) of the yoke, to be closed towards the outside by a bottom wall (230a, 230b) and open towards inside the side of the slot (11). Let us add that in each of these housings, blind vertical lights are made (24a, 24b) intended for the vertical displacement of the rollers or bearings (25a, 25b)

axle end (26).

  The sliding part (17) is slidably arranged in the middle part (8) of the device body, and has the general shape of a U, consisting of an end wall (29) and two vertical side walls (30a , 30b) whose ends carry the axis (26) with its two rollers or bearings (25a, 25b) which are guided in vertical movement

  in respective blind lights (24a, 24b).

  It is important to note that, the recessed housings (23a, 23b), as well as the blind lights (24a, 24b) only open on the side of the slot (11), and do not open outside the yoke (100). Thanks to the proposed embodiment, it can be seen that the slot (11) is completely occupied and obstructed by the lever, or at least by its embedding and pivoting part (19), and whatever its angular position. Note also that the internal faces (21a, 21b) of the yoke (100) are always and totally in contact with the transverse faces (222a, 22b) of the embedding part of the lever. thus, the control and connection means (18a, 18b, 17, 30a, 30b, 25a, 25b) are completely

  sheltered and inaccessible from the outside.

  Of course, the invention is not limited to the embodiments described and shown by way of examples, but it includes

  also all technical equivalents and their combinations.

Claims (3)

  1. Clamping device (1) intended to retain a construction part (5) to be machined or welded, device of the type comprising a lever (2) pivotally mounted in a yoke (100) of a device body (4) to be pivotally actuated by the displacement of a piston (6), between a first position (A) called the inactive release position, and a second position (B) called the active retaining position, said lever being connected to the piston (6 ) by means of control and connection means comprising a sliding part (17) integral in movement with the piston, and which is connected to the lever by means of at least one connecting rod (18a, 18b), characterized in that the lever (2) comprises an embedding and pivoting part (19) which occupies   entirely the slot (11) of the yoke (100).   2. Clamping device (1) according to claim 1, characterized in that the control and connection means comprise two connecting rods (18a, 18b) which are provided in recessed housings (23a, 23b) produced in the internal faces (21a, 21b) of the two side walls (10a, 10b) of the yoke (100, said housings not opening out outside.   3. Clamping device (1) according to claim 2, characterized in that the sliding control part (17) is arranged to slide in the middle part (8) of the device body, and has the general shape of a U, consisting of an end wall (29) and two vertical side walls (30a, 30b) whose ends carry the axis (26) with its two rollers or bearings (25a, 25b) which are guided in vertical movement in respective blind lights (24a, 24b), lights which do not not open outwards.