Fluid passage connection device

A fluid passage connection device includes a positioning mechanism that incorporates a male coupler attached to a stationary base member and a female coupler attached to a movable member, and that positions the movable member with respect to the base member so that it becomes possible to connect the male and female couplers, and a clamping mechanism that drives the movable member in order to clamp and fix the movable member with respect to the base member by the elastic force of a spring, and that also releases this clamping with the hydraulic pressure of a hydraulic cylinder; and the male coupler has a connection sleeve that is driven to retract by hydraulic pressure and is driven to advance by a spring, with a hydraulic passage being provided that interconnects a hydraulic pressure operation chamber of the connection sleeve and an unclamping hydraulic chamber of the hydraulic cylinder.

TECHNICAL FIELD

The present invention relates to a fluid passage connection device; and more particularly relates to such a device incorporating a positioning mechanism and a clamping mechanism that position and clamp a movable member to which a second coupler is attached with respect to a base member to which a first coupler is attached, and with which the first and second couplers can be automatically connected and separated by the application of fluid pressure supplied to the clamping mechanism.

BACKGROUND OF THE INVENTION

In, for example, the technical field of machining, it is often the case that a plurality of hydraulic clamp devices are fitted to a work pallet, and, in a state with the work being fixed by these clamp devices, the work is machined by a machining center. Many hydraulic clamp devices are driven to clamp by hydraulic pressure or by the elastic force of a spring, and are unclamped by hydraulic pressure. And there are provided a mechanism for positioning a work pallet to which the hydraulic clamp device is provided with respect to a base member and a clamping mechanism for fixing it there, and a fluid passage connection device that connects and separates a hydraulic passage for hydraulic pressure supplied to and vented from the work pallet.

In Patent Document #1, for a work pallet that can be fitted to or removed from a table of a machining center and for that table, there is disclosed a device provided with a positioning and fixing mechanism that positions and fixes the work pallet with respect to the table, and with a fluid passage connection device that connects a fluid passage. This fluid passage connection device includes a table side female coupler and a pallet side male coupler, and these male and female couplers incorporate valve mechanisms that are closed by springs, so that the pallet side male coupler may be separated from the female coupler while still maintaining a state in which fluid pressure is still remained.

And, in a device for fluid linking device described in Patent Document #2, each one of an almost symmetric pair of couplers incorporates a check valve that includes a steel ball provided at the tip end portion of that coupler, and a spring that biases the check valve to close it; and, when these two couplers contact against one another, the two steel balls shift one another backwards in mutually opposite directions and put the valves to their opened states, so that the fluid passage is put into the communicating state.

Patent Document #1: Japanese Laid-Open Patent Publication 2003-117748

Patent Document #2: Japanese Laid-Open Patent Publication 2003-4191

In such a case in which predetermined numbers of workpieces consisting of plural pairs of two symmetric types are to be machined in order, such as with automobile components or the like, it is not unusual for there to be a requirement for changing the location in which the hydraulic clamp device is positioned on the work pallet, according to the type of the workpiece. In this case, the clamp unit provided on the work pallets is equipped with a clamp device whose position needs to change, so that a mechanism for positioning and fixing the clamp unit on the work pallets, and a fluid passage connection device for supplying hydraulic pressure to the clamp unit, are also provided; and, by relocating this clamp unit, it is anticipated to vary the location in which the clamp device is positioned.

When changing the location of the clamp unit on the work pallet, the position of the clamp unit is changed manually, the clamp unit is fixed by the positioning and fixing mechanism after having been positioned, and then the fluid passage connection device is connected. If at this time, from before the clamp unit is positioned and fixed, the movable connection members of the male and female couplers of the fluid passage connection device are already in the advanced state, then there is a fear that, during relocation of the clamp device, the clamp unit or the like may collide with these movable connection members and cause damage to them.

Moreover, if the fluid passage connection device described in Patent Documents #1 or #2 is employed, then, when connecting the male and female couplers, it is necessary to press the male and female couplers together in the direction to approach one another with a strong force against the elastic force of the springs in the valve mechanisms that bias their valve members, and against the resistance of the fluid pressure enclosed in the clamp device which acts on the valve members; and this task of connection necessitates a considerable amount of labor and time. In this case it is easy for the clamp unit to be affected by its own weight, since the male and female couplers are connected by the weight of the clamp unit itself and by manual pressure, and it is difficult to enhance the freedom in design.

Moreover, when relocating the clamp unit after use, there is a danger that damage may be caused to either or both of the male and female couplers during separation of the male and female couplers, if the male and female couplers do not separate perfectly when the positioning of the clamp unit is released, or when the fixing by the fixing means is released.

Objects of the present invention are: to provide a fluid passage connection device with which there is no fear of damage to a male coupler or to a female coupler; to provide a fluid passage connection device which is capable of reliably and smoothly connecting the male coupler and the female coupler; and to provide a fluid passage connection device which is capable of automatically connecting the male coupler and the female coupler.

The fluid passage connection device according to the present invention comprises a first coupler fitted to a stationary base member and a second coupler that can be connected to the first coupler and that is fitted to a movable member, constituted so as to connect and separate a fluid passage through the first coupler and the second coupler, and is characterized by comprising: a positioning mechanism for positioning the movable member with respect to the base member, so that it becomes possible for the first coupler and the second coupler to connect together; and a clamping mechanism that clamps the movable member with respect to the base member with an elastic force of an elastic member or an enclosed compressed gas, and that releases this clamping with a fluid pressure of a fluid pressure cylinder; and in that: the first coupler comprises a connection member that is provided so as to be shiftable in its axial direction and connects a fluid passage in an engaged state with the second coupler, a spring that elastically biases the connection member so as to project, and a fluid pressure operation chamber that applies a fluid pressure to drive the connection member so as to retract; and a fluid passage is provided in the base member, making an unclamping fluid chamber of the fluid pressure cylinder communicate with the fluid pressure operation chamber.

When the first coupler and the second coupler are to be connected together, the movable member is positioned with respect to the base member by the positioning mechanism, and then the movable member is fixed with respect to the base member by the clamping mechanism. The clamping mechanism is driven for clamping by the elastic force of the elastic member or the enclosed compressed gas, and its clamping is released by the fluid pressure in the fluid pressure cylinder. The first coupler, which is fitted to the base member, comprises the connection member that is provided so as to be shiftable in its axial direction and connects the fluid passage in an engaged state with the second coupler, the spring that elastically biases the connection member in its direction to project, and the fluid pressure operation chamber that applies a fluid pressure to drive the connection member in its direction to retract.

Since the fluid passage is provided that makes the unclamping fluid chamber of the fluid pressure cylinder communicate with the fluid pressure operation chamber, accordingly, when the clamping of the clamping mechanism is to be released, and when hydraulic pressure is supplied to the fluid passage, initially the connection member shifts to retract so that the first and second couplers are separated, and thereafter the clamping mechanism releases its clamping after the fluid pressure has sufficiently risen.

When the clamping mechanism is to be put into the clamped state, when the fluid pressure in the fluid passage is vented, since the elastic force of the clamping mechanism is a strong force, initially the clamping mechanism goes into its clamped state, and thereafter, after the fluid pressure in the fluid pressure operation chamber has sufficiently decreased, the connection member shifts in its projection direction due to the elastic force of the spring, and the male and female couplers go into the connected state.

SUMMARY OF THE INVENTION

According to the fluid passage connection device of the present invention, since the first coupler which is fitted to the base member comprises the connection member that is provided so as to be shiftable in its axial direction and that connects the fluid passage in an engaged state with the second coupler, the spring that elastically biases the connection member in its direction to project, and the fluid pressure operation chamber that applies a fluid pressure to drive the connection member in its direction to retract, and since the fluid passage is provided that makes the unclamping fluid chamber of the fluid pressure cylinder of the clamping mechanism communicate with the fluid pressure operation chamber, accordingly, when the clamped state of the clamping mechanism is to be released, when fluid pressure is supplied to the fluid passage, initially the connection member shifts to retract and the first and second couplers are automatically separated, and thereafter, after the fluid pressure has risen sufficiently, the clamping mechanism goes into its unclamped state. Due to this, it is possible to separate the first and second couplers automatically and reliably and smoothly, and it is possible reliably to prevent damage to the first and second couplers during the unclamping procedure.

And when the hydraulic pressure in the fluid passage is vented in order to put the clamping mechanism into its clamped state, since the elastic force of the clamping mechanism is a strong force, initially the clamping mechanism goes into its clamped state, and thereafter the connection member automatically shifts in its projection direction due to the elastic force of the spring, and the first and second couplers go into their connected state. Due to this, it is possible to connect the first and second couplers automatically and reliably and smoothly, and it is possible reliably to prevent damage to the first coupler during the clamping procedure.

And furthermore, since the positioning mechanism is provided, and since the first and second couplers are only connected together after the movable member has been accurately positioned with respect to the base member, accordingly it is possible to enhance the durability of the first and second couplers. Furthermore, since the clamping mechanism is provided that fixes the movable member with respect to the base member, accordingly it is also possible to clamp the movable member automatically with respect to the base member, and to unclamp it.

In addition to the structure of the present invention as described above, it would also be acceptable to arrange to employ various further structures, as follows.

(1) When the clamping mechanism is in its unclamped state, fluid pressure may be charged into the fluid pressure operation chamber of the first coupler, and thereby the connection member may be maintained in its retracted position. According to this structure, it is possible to anticipate prevention of damage to the connection member.

The male coupler81comprises a case83that is fixed in an installation hole in the pallet main body1by being screwed thereinto, a connection sleeve84that is installed in the case83so as to be capable of being raised and lowered along its axial direction, two compression springs85that elastically bias the connection sleeve84upwards, a movable valve member86that is installed in the upper half portion of the connection sleeve84so as to be capable of being raised and lowered, a guidance member84that is fixed in the connection sleeve84and guides the movable valve member86, and a compression spring88that elastically biases the movable valve member86upwards. This connection sleeve84corresponds to the “connection member” in the claims.

(3) When fluid pressure is supplied to the unclamping fluid chamber in order to change over the clamping mechanism from its clamped state to its unclamped state, the unclamped state may be established after the connection member has been changed over to its retracted position by the fluid pressure in the fluid pressure operation chamber. According to this structure, it is possible to anticipate prevention of damage to the connection member during unclamping.

(4) The spring that elastically biases the connection member may be a spring that generates an elastic force weaker than an elastic force of the elastic member or the enclosed compressed gas for clamping. According to this structure, when changing over the clamping mechanism to its unclamped state, the clamping mechanism changes to its unclamped state after, initially from the low fluid pressure stage, the connection member has shifted to its retracted position and the first and second couplers have separated. Thus, during unclamping, it is possible to anticipate prevention of damage to the first and second couplers.

(5) An air nozzle for detecting seating and a fluid pressure type clamp device may be provided to the movable member; and, as the fluid passage that is connected and separated, there may be provided two fluid pressure passages of two systems for the fluid pressure type clamp devices, and one air passage of one system for an air nozzle. According to this structure, by providing these three passage connection devices, it is possible to connect and to separate the two hydraulic conduits of the two systems and also the air passage of the one system.

DESCRIPTION OF NUMERALS

DESCRIPTION OF THE PREFERRED EMBODIMENTS

In the following, best modes for implementation of the “fluid passage connection device” according to the present invention will be explained on the basis of embodiments.

As shown inFIGS. 1 through 5, a work pallet WP is a device that is loaded onto a machining center in a state in which a workpiece W is fixed thereto by a plurality of clamp devices4and by a clamp device4A of a clamp unit3, for supplying the workpiece W to a machining process.

The work pallet WP comprises a pallet main body1, two clamp fixing zones2provided at the left side portion inFIG. 1of the pallet main body1, a clamp unit3that is installed to one of these clamp fixing zones2, two clamp devices4fixedly provided at the right side portion inFIG. 1of the pallet main body1, and two workpiece support members5that correspond to the two clamp devices4.

While a first workpiece W is shown inFIGS. 1 and 2, if a second workpiece that is different from this first workpiece W is to be mounted instead of this first workpiece W, then the clamp unit3is installed to the clamp fixing zone2at the upper left ofFIG. 1.

As shown inFIGS. 1 and 2, each of the clamp devices4comprises a clamp main body10, a spacer block11, a clamp arm13that is fitted at the upper end of an output shaft12, and a bolt member14that is attached at the tip end portion of the clamp arm13. The clamp main body10is fixed to the pallet main body1via the spacer block11. And the clamp main body10is a known turn type (twist type) clamp device that incorporates a hydraulic cylinder comprising a clamping hydraulic chamber that drives the output shaft12downwards for clamping and an unclamping hydraulic chamber that drives the output shaft12upwards for unclamping, and a turning mechanism (twisting mechanism) that causes the output shaft12to turn through, for example, 90. degree. in the clockwise direction when the output shaft12shifts from the clamp position to the unclamp position, and so on.

An air nozzle for detecting seating of the workpiece W is provided at a central portion of the workpiece support member5. Hydraulic passages for supplying and venting hydraulic pressure to and from the hydraulic cylinder of the clamp device4and an air passage for supplying pressurized air to the air nozzle are formed in the interior of the pallet main body1, and are connected as appropriate to an external hydraulic pressure supply source and to an external air pressure supply source. The clamp device4described above is only one example; instead of this clamp device4, it would be possible to apply various types of clamp device that are capable of fixing a workpiece W.

As shown inFIGS. 1 through 6, the clamp unit3comprises a base plate20made of a thick plate, the clamp device4A and a workpiece support member5A that are fitted to the upper surface of this base plate20, and a fluid passage connection device30that includes the above clamp fixing zone2and is provided to the pallet main body1and to the base plate20. An air nozzle5afor detecting seating of the workpiece W is provided at a center portion of the workpiece support member5A. It should be understood that the base plate20corresponds to the “movable member”, while the pallet main body1corresponds to the “base member” in the claims.

The clamp device4A comprises a clamp main body10A, a clamp arm13A that is fitted to the upper end of an output shaft12A, and a bolt member14A that is attached at the tip end portion of the clamp arm13A. This clamp main body10A is fixed to the base plate20. This clamp main body10A is a known turn type (twist type) clamp device that incorporates a hydraulic cylinder comprising a clamping hydraulic chamber for driving the output shaft12A downwards to clamp the workpiece W and an unclamping hydraulic chamber for driving the output shaft12A upwards to unclamp the workpiece W, and a turning mechanism that causes the output shaft12A to turn through, for example, 90° in the clockwise direction when the output shaft12A shifts from the clamp position (refer toFIG. 4) to the unclamp position (refer toFIG. 5), and so on. However, the hydraulic clamp device4A described above is only one example; instead of this clamp device4A, it would be possible to apply various types of clamp device that are capable of fixing a workpiece W.

As shown inFIGS. 7 through 9, the above fluid passage connection device30comprises a pair of positioning mechanisms40that position the base plate20with respect to the pallet main body1, a pair of clamping mechanisms60that fix the base plate20with respect to the pallet main body1in an attachable and detachable manner, and three coupler mechanisms80.

As shown inFIGS. 1 through 9, the pair of positioning mechanisms40are arranged on opposite sides of the three coupler mechanisms80, and these positioning mechanisms40have the same structure; accordingly, just one of these positioning mechanisms40will be explained.

As shown inFIGS. 7 through 9, the positioning mechanism40comprises a support base41that is installed on the pallet main body1, and a locator ring42that is fixed to the lower surface of the base plate20.

The support base41comprises a tubular portion43that is fitted into a fitting aperture of the pallet main body1, a circular plate portion44that extends at the upper end of the tubular portion43and is contacted against and fixed to the upper surface of the pallet main body1, a tapered barrel portion45that extends upwards from the center portion of the circular plate portion44, a tapered inner circumferential surface46that is formed on the inner circumferential surface of the central hole of the locator ring42, an annular lower end reference surface47that is formed at the lower end of the locator ring42, and a Z direction reference surface48formed at the upper surface of the circular plate portion44that receives and stops the lower end reference surface47.

The outer circumferential surface of the tapered barrel portion45is formed as a tapered outer circumferential surface with the diameter reducing upwards, and the tapered inner circumferential surface46is formed so as to be capable of fitting closely over the tapered outer circumferential surface of the tapered barrel portion45. And, in a state in which the lower end reference surface47is closely contacted against the Z direction reference surface48, the tapered inner circumferential surface46is contacted closely against the tapered outer circumferential surface of the tapered barrel portion45. It should be understood that the tapered inner circumferential surface46contacts closely against the tapered outer circumferential surface of the tapered barrel portion45, via minute elastic deformation of the tapered barrel portion45in the direction to reduce its diameter. Due to this, it is possible to position the locator ring42with respect to the support base41in the horizontal direction and in the vertical direction with high accuracy.

As shown inFIGS. 7 through 9, the clamping mechanism60comprises a hydraulic cylinder61that is formed in the interior of the support base41, a piston member62thereof, and a ball lock mechanism63.

The piston member62is fitted in a cylinder bore, and a plurality of laminated coned disk springs64are fitted in an annular spring holding chamber, and drive the piston member62downwards for clamping. An unclamping hydraulic chamber61ais defined at the lower side of the piston member62, and a hydraulic passage65is formed in the pallet main body1for supplying and venting hydraulic pressure to and from this unclamping hydraulic chamber61a, with this hydraulic passage65being connected to a hydraulic pressure supply source not shown in the figures. Additionally, “hydraulic pressure” means pressurized oil in this specification.

The ball lock mechanism63comprises a plurality of steel balls67that are installed into a plurality of containing apertures in a cylinder portion66that extends upwards from the upper end of the tapered barrel portion45and that are movable in the radial direction, a plurality of concave portions68that are formed on an external circumferential portion of a portion of a piston rod62aof the piston member62that is near its upper end, and an annular engagement portion69consisting of a tapered surface formed on an internal circumferential portion of an upper portion of the central hole of the locator ring42. These concave portions68include sloping concave portions for driving the steel balls67outwards in the radial direction, and concave retraction portions for allowing the steel balls67partially to retract inwards in the radial direction.

The clamping mechanism60shown inFIG. 7is shown in its unclamped state, and the steel balls67are partially retracted into the concave retraction portions, and do not project to the exterior of the outer circumferential surface of the cylinder portion66. In this unclamped state, it is possible for the base plate20to be shifted upwards. And the clamping mechanisms60shown inFIGS. 8 and 9are shown in their clamped state, and the steel balls67are driven by the sloping concave portions outwards in the radial direction, and are pressed and clamped against the annular engagement portion69. It should be understood that, instead of the annular engagement portion69, it would also be acceptable to arrange to form a concave groove that corresponds to the each of steel balls67.

In order to blow away cutting chips adhering to the lower end reference surface47, to the Z direction reference surface48, to the tapered inner circumferential surface46, and to the tapered outer circumferential surface of the tapered barrel portion45with pressurized air, a plurality of air nozzles70and a plurality of air nozzles71are formed, and pressurized air can be supplied from an air passage70ato this plurality of air nozzles70. Moreover, pressurized air can be supplied via an air passage71aand a check valve2to the plurality of air nozzles71.

As shown inFIGS. 7 through 9, among the three coupler mechanisms80, two of the coupler mechanisms80are mechanisms that connect and separate hydraulic passages of two systems by which the clamping hydraulic chamber and the unclamping hydraulic chamber of the clamp device4A are supplied and vented. The other remaining coupler mechanism80is a mechanism that connects and separates an air passage by which pressurized air is supplied to the air nozzle5aof the workpiece support member5A. Since these three coupler mechanisms80are mutually similar, only one of these coupler mechanisms80will be explained.

As shown inFIGS. 7 through 9, this coupler mechanism80comprises a male coupler that is provided to the pallet main body1and a female coupler82that is provided to the base plate20. This male coupler81corresponds to the “first coupler”, and the female coupler82corresponds to the “second coupler” in the claims.

The male coupler81comprises a case83that is fixed in an installation hole in the pallet main body1by being screwed thereinto, a connection sleeve84that is installed in the case83so as to be capable of being raised and lowered along its axial direction, two compression springs85that elastically bias the connection sleeve84upwards, a movable valve member86that is installed in the upper half portion of the connection sleeve84so as to be capable of being raised and lowered, a guidance member84that is fixed in the connection sleeve84and guides the movable valve member86, and a compression spring88that elastically biases the movable valve member87upwards. This connection sleeve84corresponds to the “connection member” in the claims.

The lower portion of the connection sleeve84is formed as a piston portion84ahaving somewhat larger diameter, so that an annular hydraulic pressure chamber89that applies hydraulic pressure to the piston portion84ais defined, with this hydraulic pressure operation chamber89being connected to the hydraulic passage65via a hydraulic passage90. As shown inFIG. 7, in the state in which hydraulic pressure in the hydraulic pressure operation chamber89is operating, the connection sleeve84is in the lowered state as shown in the figure; and, when the hydraulic pressure in the hydraulic pressure operation chamber89is vented, the connection sleeve84is raised by the biasing force of the spring85, and is caused to project as shown inFIG. 9. A fluid passage91(a hydraulic passage or an air passage) is formed in the pallet main body1, and this fluid passage91is connected to a passage in the male coupler81, so as to constitute a fluid passage91ato the base plate20. A connecting barrel portion84bis formed at the upper end portion of the connection sleeve84, and is inserted into the female coupler82and connected thereto. Moreover, a plurality of slits are formed upon the external circumferential portion of a guard portion of the movable valve member86, in order to allow the passage of fluid.

As shown inFIGS. 7 through 9, the female coupler82comprises a case100that is fixed into an installation hole in the base plate20by being screwed thereinto, a barrel member101that is fitted into the case100and fixed therein, a movable barrel102that is installed in the barrel member101and is capable of being raised and lowered, a fixed valve member103that is fixed in the barrel member101, and a compression spring104that is installed between the fixed valve member103and the movable barrel102and elastically biases the movable barrel102downwards. When the coupler mechanism80is in its separated state, as shown inFIG. 7, the movable barrel102drops to its lower limit position, and the fluid passage is closed by the fixed valve member103and by a seal member105that is provided to the movable barrel102.

As shown inFIG. 9, when the connection sleeve84of the male coupler81is in its raised position (i.e. in the projecting state), and the connecting barrel portion84bof the connection sleeve84is inserted into the female coupler82, along with the movable barrel102rising and the valve portion of the female coupler82opening, also the valve portion of the male coupler81opens, so that the fluid passage within the male coupler81and the fluid passage within the female coupler82are connected together.

The operation and the advantages of the fluid passage connection device30described above will now be explained.

When a first workpiece W is fixed, the clamp unit3is used in its state in which it is fixed as shown inFIG. 1. By way of example, a case will be explained in which, after a first machining process on the first workpiece W has been completed, in order to fix a second workpiece, the clamp unit3is to be attached at the position at the upper left, as shown by the chain line in the figure. First, the pair of clamping mechanisms60are in their clamped states due to the elastic force of the coned disk springs64, and the hydraulic pressures in their unclamping hydraulic chambers61aare vented, as shown inFIG. 9.

Initially, the fluid supplied to the fluid passage91is vented, so that it is ensured that the fluid does not leak out, even if each of the three coupler mechanisms80is separated. Next, when the hydraulic pressure supply source is operated and hydraulic pressure is supplied to the hydraulic passage65in order to bring the clamping mechanisms60from their clamped states (refer toFIG. 9) to their unclamped states (refer toFIG. 7), hydraulic pressure is supplied to the unclamping hydraulic chambers61aand to the hydraulic pressure operation chambers89, and the connection sleeves84are changed over to their retracted positions due to the hydraulic pressure in the hydraulic pressure operation chambers89, so that thereafter the mechanisms60go into their unclamped states.

When these unclamped states are established, the piston members62are elevated, the steel balls67are partially retracted into the concave portions68and are pulled inwards further than the outer circumferential surface of the cylinder portions66, and the close mutual engagements of the tapered outer circumferential surfaces of the tapered barrel portions45and the tapered inner circumferential surfaces46are separated (refer toFIG. 7) by the wall surfaces of the concave apertures20aof the base plate20being pressed with the ends of the piston members62.

And, since the springs85elastically biasing the connection sleeves84are springs that are remarkably weaker than the coned disk springs64for clamp driving, accordingly, at a time point partway through the rising of the pressure of hydraulic pressures in the hydraulic passages65, the connection sleeves84change over to their lowered retracted positions (refer toFIG. 8), and thereafter the clamping mechanisms60go into their unclamped states (refer toFIG. 7). And, while the clamping mechanisms60are in their unclamped states, hydraulic pressure is supplied to the hydraulic pressure operation chambers89of the male couplers81, so that the connection sleeves84are maintained in their retracted positions.

Next, while the clamp unit3is moved to the clamp fixing zone2at the upper left ofFIG. 1, hydraulic pressure is supplied to the hydraulic passage65, the hydraulic chambers61a, and the hydraulic pressure operation chambers89of this clamp fixing unit3as well. Due to this, the piston members62of the clamping mechanisms60are brought to their unclamped positions, and the connection sleeves84are in their retracted positions. Then the clamp unit3is lowered onto the clamp fixing unit2from above, and is set upon it as shown inFIG. 7. Next the hydraulic pressure in the hydraulic passage65is vented, in order to change over the clamping mechanisms60from their unclamped states to their clamped states, and as shown inFIG. 8the hydraulic pressures in the unclamping hydraulic chambers61aare vented, so that the piston members62are lowered and go into their clamped states due to the elastic force of the strong coned disk springs64.

Although at this time the clamping mechanisms60go into their clamped states rapidly, since residual hydraulic pressures created due to the lowering operation of the piston members62are generated in the hydraulic passage65and in the hydraulic pressure operation chambers89, accordingly the connection sleeves84are held in their retracted positions as shown inFIG. 8; and thereafter, when the hydraulic pressures in the hydraulic passage65and the hydraulic pressure operation chambers89decrease sufficiently, the connection sleeves84rise due to the elastic force of the springs85, and the connecting barrel portions84bof the connection sleeves84thrust themselves into the female couplers82, so that the valves of the male couplers81and the valves of the female couplers82are opened, and the male couplers81and the female couplers82are put into their connected states as in the figure.

Due to the positioning mechanisms40, the clamping mechanisms60are put into their clamped states with respect to the pallet main body1in the state in which the base plate20of the clamp unit3is accurately positioned in the vertical direction and in the horizontal direction, and in this state it becomes possible to insert the connection sleeves84of the fluid passage connection devices30into the female couplers82smoothly in order to connect the male and female couplers81and82, since now the biasing force of the springs85is not a strong force, so that, while allowing the male and female couplers81and82to be made more compact, it is also possible to connect the male and female couplers81and82in a proper state without performing any vehement action, and thus it is possible to enhance the durability of the male and female couplers81and82.

Since, when putting the clamping mechanisms60into their clamped states, the male and female couplers81and82are put into their connected state after the initial changeover to the clamped state, accordingly it is considered that damage to the male and female couplers81and82will be prevented, and so the durability can be enhanced. And since, when putting the clamping mechanisms60into their unclamped states, the connection sleeves84of the male couplers81are changed over to their retracted positions initially, and the clamping mechanisms60are put into their unclamped states after the separated states of the male and female couplers81and82have been established, accordingly it is considered that damage to the male and female couplers81and82will be prevented, and so the durability can be enhanced.

And, since the male and female couplers81and82are built so as to be connected together and to be separated in their states in which the fluid pressures interior to them and in the fluid passage91are vented, accordingly it is possible to anticipate that the springs in the male and female couplers81and82can be made more compact, in other words that the male and female couplers81and82can be made more compact; and moreover it is possible to anticipate that connection and separation of the male and female couplers81and82can be made more smooth.

In the description of this embodiment, to structural elements that are similar to ones of the first embodiment, the same reference numerals are appended, and explanation thereof will be omitted, with only the structures that are different being explained. As shown inFIG. 10, with the clamping mechanism60A of this fluid passage connection device30A, it is arranged for its piston member62A to be biased downwards by the elastic force of compressed nitrogen gas enclosed in an annular gas storage chamber64A (for example at a gas pressure of around 7 to 10 MPa). In order to charge the compressed nitrogen gas into this gas storage chamber64A, gas passages74and75are formed in the piston rod portion of the piston member62A, and a charging valve76for charging the compressed nitrogen gas is installed at the upper end portion of this gas passage74. The compressed nitrogen gas enclosed in the gas storage chamber64A is sealed in by seal members64aand64b. With this clamping mechanism60A, the structure is simplified, since it is possible to omit the superimposed layers of coned disk springs. This fluid passage connection device30A operates in a similar manner to the fluid passage connection device30of the first embodiment, and provides similar advantages.

In the description of this embodiment, to structural elements that are similar to ones of the first embodiment, the same reference numerals are appended, and explanation thereof will be omitted, with only the structures that are different being explained. As shown inFIGS. 11 and 12, with the coupler mechanism80B of this fluid passage connection device30B, the female coupler81B is attached to the pallet main body1, while the male coupler82B is attached to the base plate20. The female coupler81B corresponds to the “first coupler”, while the male coupler82B corresponds to the “second coupler” in the claims.

This female coupler81B comprises a case110, a connection sleeve111that is installed within the case110so as to be capable of rising and dropping therein (this corresponds to the “connection member”), a valve member112that is installed within the upper half portion of this connection sleeve so as not to be capable of shifting relatively thereto, a movable barrel member114that supports a seal member113at its upper end portion and that is installed between the valve member112and the connection sleeve111so as to be capable of rising and dropping therein, a spring115that biases the movable barrel member114upwards with respect to the valve member112, a spring reception ring116, a stop ring117that receives and stops the spring reception ring116, a spring118that biases the connection sleeve111upwards with respect to the case110, an annular hydraulic pressure operation chamber119that applies hydraulic pressure to the annular upper surface of a piston portion111aof the connection sleeve111, and so on. And the hydraulic pressure operation chamber119is connected to and communicates with the hydraulic passage65that supplies and vents hydraulic pressure to and from the above unclamping hydraulic chamber61aof the hydraulic cylinder61.

The male coupler82B comprises a case120, a movable valve member121that is installed within the case110so as to be capable of rising and dropping therein, a spring reception and guidance member122that is installed within the upper portion of the case120, a spring123that is installed between this spring reception and guidance member122and the movable valve member121and biases the movable valve member121so as to close it, and so on. And a connecting barrel portion120ais formed at the tip end portion of the case120, and can be fitted into the upper end portion of the connection sleeve111of the female coupler81B.

When hydraulic pressure is vented from the unclamping hydraulic chamber of the hydraulic cylinder of this clamping mechanism, since the hydraulic pressure in the hydraulic passage65drops and the hydraulic pressure in the hydraulic pressure operation chamber119also drops, accordingly, as shown inFIG. 12, the connection sleeve111rises and the female coupler81B is connected to the male coupler82B. This fluid passage connection device30B operates in a similar manner to the fluid passage connection device30of the first embodiment, and provides similar advantages.

Variant examples in which the first, second, and third embodiments described above are partially changed will now be explained.

[1] As the clamp devices fitted to the clamp unit3, it would be possible to employ hydraulic pressure driven type clamp devices or air driven type clamp devices of various types and structures, different from the above clamp device. And the fluid passage connection device30is not to be considered as being limited to connecting three different fluid passages; it would be acceptable for it to be a device that connects a single fluid passage, or one that connects three or more fluid passages.

[2] With the fluid passage connection devices30,30A, and30B of the above embodiments, the positioning mechanisms40and the clamping mechanisms60,60A were built integrally, but it would also be acceptable to provide these as separate structures. And the provision of two positioning mechanisms40is not limitative; it would also be acceptable to provide one positioning mechanism, or three or more thereof. In a similar manner, the provision of two clamping mechanisms60,60A is not limitative; it would also be acceptable to provide one clamping mechanism, or three or more thereof.

[3] While in the above embodiment, by way of example, a case was explained in which the hydraulic clamp device4A and the workpiece support member5A with the air nozzle for seating detection attached were provided upon the base plate20, the present invention is not limited to the devices that are provided upon the base plate20being only a clamp device and a workpiece support portion; it would also be acceptable for them to be various types of devices that require pressurized fluid such as pressurized hydraulic fluid or air or the like.

[4] The shown structures of the male and female couplers81,81B,82, and82B are only cited by way of example; couplers of various other structures having similar functions may also be employed.

[5] Apart from the above, for a person skilled in the art, it would be possible to implement the above embodiments in various forms by supplementing various changes, and the present invention is to be considered as also including this type of variant implementation.

INDUSTRIAL APPLICABILITY

The present invention can be applied to a fluid passage connection device that connects and separates a hydraulic passage that supplies and vents hydraulic pressure to and from a work pallet of a machining center.