FR2657804A1 - AUTOMOID, GAS CLAMP FOR MISCELLANEOUS PARTS. - Google Patents

Abstract

- Immobilization of various parts. - The flange is characterized in that:. one of the variable-volume chambers is formed in the form of a capacity ensuring the containment of a charge of pressurized gaseous fluid acting to move the piston (12) in the direction of clamping between the jaw (18) and the foot (6),. and in that the other chamber (14) is in connection with a fitting (23) for connection with a circuit (24) capable of delivering in said chamber a fluid pressure developing a force greater than that generated by the gas charge . - Application to machine tool tables.

Description

I

  INDEPENDENT CLAMP FOR GAS, FOR VARIOUS PIECES

  The present invention relates to the immobilization of various parts on trays, plates, work tables or machining or any other similar media with respect to which any part must be firmly immobilized temporarily. As a preferred application, the invention relates to the immobilization of workpieces on machine tables

tools.

  The immobilization of parts on any support

  is usually done by direct or indirect mechanical clamping.

  By indirect clamping, it is necessary to consider the adaptation on the support of a clamping piece in / or on which the piece to

immobilize is adapted.

  By direct clamping, it is appropriate to consider the immobilization of the part itself directly on the table, by means of flanges exerting a clamping action of the workpiece on the support.

  The invention relates to direct clamping.

  The flanges, used to ensure direct immobilization, are generally of the mechanical type and most often comprise a bolt-type anchoring foot that can be fitted into a T-type groove presented by the machine. support The mechanical flange comprises in elevation from the foot a kind of tie rod or the like, or a body supporting a movable jaw whose position can be adjusted by a

screw or knee control.

  The blocking of the workpiece to be immobilized by means of a toggle device is not satisfactory because of the pressure

  relatively low likely to be exercised.

  A screw drive makes it possible to ensure immobilization capable of withstanding high stresses, but its relatively long commissioning does not allow adaptation in high-frequency work sequences. In addition, the clamping force is only dependent on the manual action of the operator, so that variable pressure stresses can occur with all the damaging consequences that may be attached to a tightening too much

weak or too strong.

  In all areas where the immobilization of a part must be ensured, the need has therefore been felt to have a clamping clamp that can be quickly actuated in clamping and unclamping, capable of exerting a clamping force known and constant on the part to immobilize, of simple design and

robust, and certain reliability.

  To meet this need, the prior art has recommended the use of hydraulically controlled flange. In this regard, in particular US Pat. No. 4,504,046 and DE-C 3,736,421, each comprising, in a support body, a double acting hydraulic piston, whose rod acts by a wedge on a ramp controlling the actuation of a guided clamping jaw

in the body.

  Such solutions certainly represent an appreciable development which, however, does not yet give any satisfaction.

for the following reasons.

  If the hydraulic flanges have a faster action than the mechanical flanges, on the other hand, they require to be permanently connected to two hydraulic circuits whose size is always inconvenient.

  dependence removes any possibility of autonomous use.

  The provision of a hydraulic clamping pressure must be maintained throughout this phase, resulting in a certain energy expenditure for a period equivalent to that of

the clamping phase.

  Since the hydraulic clamping pressure is applied for long periods of time, it is imperative to build the flange with high quality components, able to withstand durably without leakage to the imposed stress This requirement certainly raises the cost of manufacture, but also maintenance

such flanges.

  The present invention aims to solve the above drawbacks, by proposing an autonomous gas-type clamping flange, made in the form of a functionally autonomous elementary assembly, which can be adapted to all the fields of application, whenever it is necessary to temporarily secure the immobilization of a room or any object

on a support.

  To achieve the above objectives, the object of the invention comprises a flange body delimiting a cylinder, a foot of connection and anchor carried by the body, a piston housed in the cylinder in which it delimits two chambers to inversely variable volumes, and a clamping jaw partially associated with the piston, characterized in that: one of the variable volume chambers is constituted in the form of a closed capacity, ensuring the sealed confinement of a gaseous fluid charge under pressure, acting to move the piston in the direction for which there is a clamping action between the jaw and the foot, and in that the other chamber is in connection with a connection connection with a circuit capable of delivering in said chamber, in a controlled manner, a fluid pressure developing a force greater than that

  generated by the contained gaseous charge.

  Various other features emerge from the

  description given below with reference to the accompanying drawings which

  show, by way of non-limiting examples, forms of

  accomplishment of the object of the invention.

  FIG. 1 is a cutaway of a first example

  embodiment of the flange according to the invention.

  FIG. 2 is a transverse view taken according to the

line II of fig 1.

  FIGS. 3 and 4 are diagrammatic views showing two variant embodiments of the example according to FIG.

fig 1.

  FIG. 5 is a sectional elevation of another form of

  embodiment of the flange according to the invention.

  Fig. 6 is a sectional elevation illustrating a

  third embodiment of the subject of the invention.

  FIG. 7 is a plan view taken according to the

line VII-VII of FIG.

  FIG. 8 is a cross-section taken according to the

line VIII-VIII of fig 6.

  Fig 9 is a sectional elevation of a fourth form

  of accomplishing the object of the invention.

  Figs 10 to 12 are sections respectively taken

  along the lines X-X to XII-XII of FIG.

  FIG. 13 is a partial section taken according to the

line XIII-XIII of fig 12.

  Fig. 14 is an exploded perspective view illustrating the particular conformation of two constituent elements of

the example according to FIGS. 9 to 13.

  FIGS. 1 and 2 show a first exemplary embodiment of a gas self-contained clamping clamp 1, designed according to the invention for immobilizing a part 2 with respect to a support 3 illustrated in the form of a machine tool table. Conventionally, such a table comprises in place of the grooves 4 of the inverted tee type, which are used to ensure the adaptation of the flange 1 for this purpose, the flange 1 comprises a body 5 which directly forms to its base a foot of connection and anchorage 6 of the type to bacon, to be even engaged in

  a groove 4 of complementary profile.

  The body 5 preferably has a stem shape and has an upper portion 7 extending cantilevered from the body 5 and parallel to the foot 6 The upper portion 7 defines a cylinder 8 closed, in particular by a plug 9 removable or not The cylinder 8 communicates by its bottom with a concentric bore 10 opening into a blind housing 11 opening on the face of the end portion

7 oriented towards the foot 6.

  The cylinder 8 contains a piston 12 delimiting inside the cylinder 8 two inversely variable volume chambers 13 and 14. The piston 12, which is able to slide sealingly inside the cylinder 8, is extended by a sliding rod 15 with The stem 15 forms at the end a wedge 16 protruding into the housing 11 to cooperate with a ramp 17 formed by a clamping jaw 18 slidable in the housing 11 In this example, the sliding direction xx ' clamping jaw 18 is

  perpendicular to the sliding direction y-y 'of the piston 12.

  The clamping jaw 18 preferably protrudes continuously from the lower face 7a and can be retained inside the housing 11 by any suitable technical means, such as a

  shoulder, a ring, or even an elastic return member such as 18 a.

  The ramp 17 can be formed directly by the jaw 18 or, preferably, by a nut-ball 19, spherical or substantially semicylindrical type, placed in a complementary cavity presented by the jaw 18 to offer the ramp 17 in

cooperation with corner 16.

  The chamber 13 constitutes a closed capacity in which is confined a charge of fluid, preferably gaseous, under pressure, for example introduced via a valve plug 20 closing a conduit 21 opening into

the room 13.

  The chamber 14 of the cylinder 8 communicates with a pipe 22 extended externally to the body 7 by a connection 23, preferably of the fast type, making it possible to connect the chamber 14 to a circuit 24 able to deliver, in a controlled manner, a fluid pressure. , preferably hydraulic, developing in the chamber 14 an antagonistic force greater than that generated in the chamber 13

by the gaseous charge.

  Preferably, the ramp 17 makes, with respect to a plane PP 'perpendicular to the axis x-x', an angle a complementary to the angle e presented by the corner 16. The angles a and a 'are of the type a. non-reversible actuation, that is to say that the displacement of the piston 12 in the direction of the arrow f 2 produces the sliding of the clamping jaw 18 in the clamping stroke in the direction of the arrow f 2, without a inverse mutual actuation does not

can intervene.

  Insofar as this condition is not respected, it can be envisaged to have in the chamber 13 an elastic member 25 working in the compression, always requesting the

  piston 12 in the direction of the arrow f 2.

  The operation of the flange described above

intervenes as follows.

  When it is appropriate to place the part 2 on the support or the table 3, the flange is connected by the connection 13 to the source 24 which delivers in the chamber 14 a pressurized fluid greater than that of confining the gaseous feedstock. Inside the chamber 13 the piston 12 is thus biased in the opposite direction to that of the arrow f 2, so that can intervene, directly or

  indirectly, the erasure of the clamping jaw 18.

  Such a phase preferably occurs after adaptation of the flange 1 to the table 3 by cooperation between the foot 6 and

at least one of the grooves 4.

  When the piece 2 has been placed in the required position, the source of fluid 24 is disconnected from the connection 23 to release the pressure in the chamber 14 The gas charge confined in the chamber 13 then causes the piston 12 to move in the direction The wedge 16 acts on the ramp 17 which pushes the jaw 18 in the direction of the arrow f 1, so as to exert a clamping action between the jaw and the foot 6 to tighten the blade.

  piece 2 between the table 3 and the jaw 18.

  The clamping action is exerted by the flange 1 autonomously because of the pressure of pressurized fluid trapped in the chamber 13 The immobilization of the part 2 remains effective without requiring any intervention of an operator, as long as a connection to the source 24 is not established. It should be noted that the flange according to the invention has an irreversible type of wedge and ramp mechanism which makes it possible to maintain a relative clamping force, even if the gas pressure

  accidentally falling into the room 13.

  The clamping mechanism via the wedge 16 and the jaw 18 provides a clamping stiffness which has a certain advantage in the case where the immobilization of the part 2 must undergo relatively high dynamic forces, or even generating

vibration.

  The energy required for the unbridling provided by the source 24 involves a high relative pressure which is not

  applied to the flange only in the unclamping phase.

  In addition to the energy saving achieved, this form of actuation makes it possible to reduce the high pressure that would ordinarily be required if the clamping action intervenes by connection between the chamber 13 and the source 24, replacing the

onboard gas load.

  The application of the unclamping pressure takes place in a generally very short time, so that the flange is only very slightly stressed by this pressure and can therefore be reliably and robustly carried out without the use of mobile equipment. very high technical characteristic, able to work efficiently and durably with the pressure

debridement.

  FIG. 3 shows an alternative embodiment in which the clamping action takes place directly via a moving element which consists solely of a piston 12 whose rod 15 directly forms the clamping jaw 18. irreversible bridging characteristics are not obtained due to the absence of the

corner 16 and ramp 17.

  In this embodiment, the same references designate the same component parts as those described in

relation with fig 1.

  It is the same for the variant according to Fig 4 in which the piston rod 15 passes through sealing body 5, so as to form directly by its base, the anchor foot 6 able to cooperate with at least one groove 4 In such a case, the clamping jaw 18 is constituted by a ta Lon or the body 5 which is traversed by the piston rod 15 The clamping action of the part 2 occurs between the foot 6 and the jaw 18 static . Another embodiment is illustrated in FIG. 5 in which the piston rod 15 is extended by the wedge 16 which acts on an indirect type clamping system. In this example, the wedge 16 acts on a jaw 181 internal to the housing. He who is

  closed by a cap 30 possible guide this jaw.

  A tie rod 31 bears against the jaw 181 opposite the ramp 17. The tie rod passes freely through the jaw 181. The wedge 16 through a notch 32 and the body 5 which has a heel 33 forming the jaw 18 of the example preceded in combination with the jaw 18 l Externally to the body 5, the tie has a foot 6 able to cooperate with a groove 4 The support of the tie rod on the jaw 181 is preferably provided by a threaded end 34 to adjust

the effective length of the tie rod 31.

  The clamping action of the part 2 on the support 3 occurs as previously by the action of the gaseous load pushing the piston in the direction of the arrow f 2 The wedge 16 acts on the ramp 17 to lift the jaw 181 which drives with it the tie rod 31 immobilized by the foot 6 in the groove 4 A relative downward displacement of the body 5 is in this way produced with the application of the static jaw 33 on the pressed piece 2

on the table 3.

  In this example, the wedge 16 is extended by a finger 36, able to project out of the body 5 to constitute a

  visual indicator of the state of clamping or unclamping of the flange.

  Another embodiment of the flange according to the invention is illustrated in FIGS. 6 to 8, in which the same references designate the same constituent elements as those

  described in relation to the various previous variants.

  In this embodiment, the jaw 18 is pivotally mounted on an axis 40 passing through the housing and extending parallel to the direction of movement yy 'of the piston 12 The jaw 18 occupies a plane perpendicular to the axis yy' and has a nose of clamping 41 extending externally to the body 5 A return spring 42 is preferably interposed between the body 5 and the

jaws 18.

  Preferably, as shown in FIG. 6, the body 5 is constituted in two parts, one delimiting the cylinder 8, the other 5b delimiting the guide bore 10 of the rod 12 and the housing 11 The rod 12 forms the corner 16 which cooperates

  with the ramp 17 preferably formed by the ball-nut 19.

  The clamping action of the jaw 18 is controlled, as previously said, by the displacement of the piston 12 in the direction of the arrow f 2 This displacement tilts or pivots the jaw 18 in the direction of the arrow f 3 on the axis 40, so that an action of

  clamping of the part 2 intervenes between the nose 41 and the foot 6.

  Another variant embodiment of the subject of the invention is illustrated by FIGS. 9 to 14, in which the same references designate the same constituent elements as those

previously described.

  In this example, the clamping jaw 18, whose general plane is perpendicular to the axis y-y ', is formed as a solid piece forming the nose 41 The jaw 18 comprises, in contrast to a bearing heel 43, a convex profile 44 cooperating with a complementary wall 11b of the housing 11 At the opposite of the nose 41, the jaw 18 has a stop 45 for adapting an organ

  elastic 46 working on traction and responsible for bringing back-

  jaws 18 in a position of retraction relative to the housing 11.

  The end portion of the jaw 18, opposite the nose 41, has below the edge 45 two inclined ramps 47 and 48 which occupy different planes corresponding to two directions

  orthogonal control perpendicular to the x-x 'axis.

  The ramps 47 and 48 are intended to cooperate with two complementary ramps 49 and 50 respectively formed by the wedge 16 which can be constituted directly by the piston rod 12 or by a

  independent piece, as shown in fig 14.

  Under the action of the fluid charge occupying the chamber 13, the piston 12 is displaced in the direction of the arrow f, so that the wedge 16 comes to cooperate first by the

  ramp 49 with the ramp 47 of the jaw 18.

  As can be seen from the comparison of FIGS. 12 and 13, the displacement in the direction of the arrow f 2 causes the nose 41 to extend out of the body 5 in a direction that is perpendicular to the yy axis. the cooperation of the ramp 50 with the ramp 48 tilts or pivots the jaw 18 simultaneously with its extension stroke, by pressing the heel 43 with guiding

  concomitant by cooperation of the profile 44 with the wall Mb.

  The action of the piston 12 thus produces, in a first step, an extension stroke bringing the exit of the nose 41 out of the body 5, then, then by pivoting-tilting, the tightening of the

  piece 2 between the nose 41 and the support or the table 3.

  The movement of the jaw 18 acts as said above against the action of the elastic member 46 which brings the jaw back to the original position, as soon as the piston 12 is driven in the opposite direction to that of the arrow f 1 by connecting the

  chamber 14 with the source of pressurized fluid 24.

  In this embodiment, it can be provided to adapt to the body 5 a manual control 51 to cause, if necessary, the stroke of the piston 12 in the direction

inverse to that of the arrow f 2.

  The invention is not limited to the examples described and represented, since various modifications can be made to it.

without leaving his frame.

Claims (9)

  1 self-contained gas clamping flange, for various parts, of the type comprising a flange body delimiting a cylinder, a binding and anchoring foot carried by the body, a piston housed in the cylinder in which it delimits two chambers to inversely variable volumes, and a clamping jaw partially associated with the piston, characterized in that one of the variable volume chambers is constituted in the form of a closed capacity ensuring the sealed confinement of a gaseous fluid load under pressure acting to move the piston (12) in the direction for which there is a clamping action between the jaw (18) and the foot (6), and in that the other chamber (14) is in connection with a fitting (23). ) of connection with a circuit (24) able to deliver in said chamber in a controlled manner a fluid pressure developing a force greater than that generated by the load fizzy gas.   Clamping flange according to Claim 1, characterized in that the anchoring foot (6) is formed by the body (5).   Clamping flange according to Claim 1, characterized in that the anchoring foot (6) is formed by the piston (12). 4 Clamp according to one of the   Claims 1 to 3, characterized in that the jaw (18) is formed directly by the piston (12).   5 clamp according to claim 4, characterized in that the jaw (18) comprises at least one ramp (17) with which cooperates a wedge (16) displaced by the piston (12).   Clamping flange according to claim 1 or 5, characterized in that the jaw (18) is movably mounted in one direction.   different from that y-y 'displacement of the piston (12).   Clamping flange according to Claim 6, characterized in that the jaw (18) is movable according to a   x-x 'direction perpendicular to that of the piston.   8 clamp according to claim 6 or 7, characterized in that the jaw is movable in a curved path. 9 clamp according to claim 6 or 7, characterized in that the jaw (18) is constituted by a heel (33) of the body and a movable part (181) guided in the body, cooperating with the wedge (16) and linked to a tie rod (31) passing through the   the corner and the body beyond which it forms a foot of anchorage.   Clamping flange according to claim 8, characterized in that the jaw (18) has, in cooperation with the wedge, a first ramp (47) for extending the stroke of the body against the action of an elastic member ( 46) and a second   ramp (48) of control by pivoting in clamping stroke. 11 Clamp according to one of the   Claims 5 to 10, characterized in that the angles a and a '   ramp and corner are of the non-reversible type   and in that the piston is associated with an elastic return member.