FR2613269A1 - Appliance for clamping components, particularly for machine tools - Google Patents

Abstract

The appliance is noteworthy in that it comprises a control means generating a thrust or pulling force which is decomposed into two identical forces applied simultaneously and in opposite directions on two movable jaws by means of suitable transmission means for the purpose of moving the said jaws apart or bringing them together with clamping pressure.

Description

 The invention relates to an apparatus for clamping parts, particularly for machine tools.

 The object of the invention is related to the technical sector of clamping means in general of the type vices for example, and in particular machine tool vices, centers of u se nage and similar machines.

 Selan the invention, we wanted to achieve a clamping device including to increase the clamping capacity for a minimum footprint.

 For this purpose, and according to a first characteristic, the apparatus comprises two movable jaws actuated simultaneously and in opposite directions by connection with a strong transmission means of the gearwheel type associated with two racks mounted at two diametrically opposite points of said wheel. toothed; one of the racks being secured directly to one movable jaw while 17autre is connected to a drive member itself secured to the other movable jaw.

 These and other features will become apparent from the following description.

To fix the object of the invention without however limiting it, in the appended drawings:
Figure 1 is a view illustrating in perspective the apparatus and separately the main elements of the apparatus according to the invention.

 Figure 2 is a longitudinal sectional view of the apparatus according to the invention shown in position of maximum separation of the jaws.

 Figure 3 is a cross-sectional view taken along line 3-3 of Figure 2.

 Figure 4 is a longitudinal sectional view on a smaller scale of the apparatus shown in the maximum position of approaching the jaws.

 Figure 5 is a purely schematic view illustrating another embodiment of the apparatus.

 In order to make more concrete the object of the invention, it is now described in non-limiting embodiments of embodiments illustrated in the figures of the drawings.

 The apparatus according to Figures 1 to 4 essentially comprises a base (1) of parallelepipedal shape positioned by any known means on the table of a machine tool. At one end (1a), is fastened by screw a transverse block (2) T-profile constituting in its upper part thinned (2a) a bearing for mounting freely sliding in a bore t2b) of a pusher member (3). ) which is connected on one side (3a) to an oleopneumatic or hydraulic control means not shown. This member is externally threaded at (3b) over most of its length to receive on either side of the bearing nuts (4) - (4a) for delimiting the race of the organpoussoir.On the opposite end (3c) of said member is wedged angularly a connector (5) having a threaded surface (5a) for cooperation with the threaded orifice (6a) of a vertical bar (6) whose two ends have notches (6b) positioning and screw fixing for lower (7) and upper (8) bars of rectangular or square section.

 The bars (7-8) then pass through the lower (9a) and upper (9b) guiding slots of an intermediate post (9) fixed by screw to the base and the sum of a closing flange (10).

 At the end of the bar (8) projecting from the upright, is centered and fixed a plate (11) constituting the first movable jaw equipped with a support face Vé (11a).

 The lower bar (7) extends to near the other end (lb) of the base where it traverses the guided sliding a notch (12a) made on a support (12) fixed by screw to the base. Over a length (Li) from its free end, the bar (7) has on its upper face (7a), a transverse toothing (7b) so as to form a rack.

 At the upper part of the support (12) and in alignment with the notch (9b) of the upright (9), another notch (17b) is made for the freely sliding housing of a bar (13) of rectangular section or square whose end facing the jaw (11) receives in the same manner as for the bar (8) a second movable jaw (14) with a Ve bearing surface (14a).

 Of course, the bars t8 and 13) can also directly form the movable jaws or be arranged to receive other types of reported movable jaws.

 A flange (15) is fixed on the support (12) to close the notch (12b).

 The bar (13) has on its underside a transverse toothing (13a) forming a rack which is intended as the rack (7b) to cooperate with a toothed wheel (16) housed in a blind bore (12c) of the support opening partially in the cuts (12a-12b).

 The toothed wheel is freely rotated on a shaft (17a) formed at the end of a stepped plate (17) which is fixed by screws at a recess (12d) of the bore (12c).

 It is also seen that between the upright <9) and the support (12) the bar (7) is covered by a protective casing (18). Another housing (19) is fixed at the end of the support (12) to protect the racks (7b) and (13a).

 The operation of the apparatus is now described with reference to FIGS. 2 and 4.

 It is assumed that the movable jaws are as close as possible to each other (Figure 4). We want to tighten a piece (P1). For this, it acts on the control means of the push member so that it moves back arrow F1) until the nut (4) abuts against the bearing (2). In this action, the connecting bar (6) integral with the pusher member, at the same time does the bar (8) move the movable jaw (11) along the arrow (F2), as well as the bar (7), thus the rack (7b), which causes rotation of the toothed wheel (16) in the direction of the arrow (F3), which in turn drives the bar (13) so the movable jaw (14) in the opposite direction arrow F4 ) to the bit (11).

 At this moment, the two jaws are spread apart at maximum (Figure 2). When the piece is placed between the jaws, it suffices to reverse the throttle control so that it moves in the direction of the arrow (F5) until the stop of the nut (4a) against the bearing ( 4), thus simultaneously driving the bars (8) and (7) in the direction of the arrows (F6), thus the toothed wheel (16) in the opposite direction (arrow F7) and the bar (13) in the opposite direction ( Arrow F8) to the bars (7 and 8), so that the movable jaws (11 and 14) clamp the workpiece with a force which is the counter-reaction of the application force on the push member (3).

 FIG. 5 schematically illustrates a variant embodiment in which the control member (20) with hydraulic or oleopneumatic operation is fixedly mounted on a bearing of the base, and is connected to the movable jaws (11 and 14) by means of pipes (21 and 22).

 The pipe (21) is connected to a support (23) carrying the movable jaw (11), while the pipe (22) is connected to a support (24) carrying the movable jaw (14); said jaws both mounted to slide tightly in the supports.

 According to another variant, for clamping polygonal and in particular parallelepipedal parts, provision is made to place them on the casing (1B) a sole (25) on which the pieces rest (dashed lines (FIG. 2).

 The advantages are apparent from the description, it is further emphasized, the large clamping capacity of the fact that the two jaws move simultaneously, the speed of action interesting for modern machines such as machining center, transfer machines, and balancing the clamping.

Claims (7)

-1- apparatus for clamping workpieces, especially for machine tools, characterized in that the apparatus comprises a control means generating a thrust or traction force which is broken down into two identical forces applied simultaneously and in opposite directions on two movable jaws by appropriate transmission means, with a view to their spacing or their approximation with clamping pressure. -2- clamping apparatus according to claim i, characterized in that the movable jaws (11 and 14> are controlled simultaneously and in opposite direction by connection with a transmission means gear type gear (16) associated with two racks <7b-13a) mounted at two diametrically opposite points of said gear; one of the racks (12a) being secured directly to a movable jaw (14) while the other (7b) is connected to a drive member (3) which is itself secured to the other movable jaw ( 11). -3- Clamping apparatus according to claims 1 and 2 together, characterized in that the drive member <3) is a pusher operation oleopneumatic or hydraulic, which is slidably mounted on a bearing (2) to move between two end stops (4-4a); said member is mechanically connected to the two movable jaws (11 and 14) by a connecting bar (6) carrying at its upper part the first movable jaw (11) and at its lower part the rack (7b) for controlling the rack ( 13a) of the second movable jaw (14) via the toothed wheel (16). -4- Clamping apparatus according to claims 1 and 2 together, characterized in that the rack (7b) is formed on a length (he) at the end of a bar (7) which is slidably guided in notches (9a) and (12a) respectively formed in the lower part of an inter-pillar (9) and an end support (12).  -5- Clamping device according to claims 1, 2 and 4 together, characterized in that the toothed wheel (16) is housed in a blind bore (12c) of the support (12) and mounted & free rotation on a shaft (17a ) formed at the end of a stepped plate (17) which is fixed at a recess (12d) of the bore (12c). -6- Clamping apparatus according to claims 1 and 2 together, characterized in that the movable jaws (11) and (14) are formed directly or reported at the end of bars (g) and (13) slidably guided in notches (9b) and (12b) respectively formed in the upper part of the upright (9) and the support (12); the bar (8) being secured to the connecting bar (6) as the bar (7) carrying the crimp (7b). -7- Clamping apparatus according to claim 1, characterized in that the movable jaws (11 and 14) are controlled simultaneously and in opposite direction by a member (20) for hydraulic or oleopneumatic control transmitting the pushing or pulling force by via branch pipes (21 and 22) with movable jaws slidably mounted on supports (23- 24), in order to apply to said jaws identical forces to allow their spacing or approximation with clamping pressure.