FR2620191A1 - Universal directional control valve with a slide valve - Google Patents

Abstract

Pneumatic 5/2-port directional control valve, in which the fluid switchovers are operated with the aid of a slide valve 30 which moves inside annular seals 28 held stacked up in a bore 20 by skirts 21, 22 of two lateral plugs 18, 19 able to impart to this slide valve movements in the direction F or G in order to execute fluid switchovers available on two orifices 15, 16. This directional control valve is advantageously used for monostable or bistable controlled applications.

Description

The invention relates to an associable pneumatic distributor comprising, in a body, a drawer
revolution, provided with grooves and partitions, which is axia
movable between a working position and a rest position, for each of which external cylindrical surfaces of these partitions cooperate with sealing rings concentrically stacked in a bore of the body, these grooves establishing for each of the rest and working positions fluid paths going, on the one hand, from a section of pressurized conduit to one of two outlet orifices connected to a user device, and going, on the other hand, from the other outlet orifice, to one of two sections of exhaust duct.

In known distributors, commonly known as 5/2 distributors, which are widely used in pneumatic automation systems, there is constantly a search for a reduction in the technical cost of the components because these systems call for a relatively large number of this type of components. In these systems there is also a growing need for distributors with different properties, in particular to be able to
be adapted to the physical nature of control signals (pneumatic, electrical, magnetic, etc.) and also to take into account the greatest possible number of configurations of the systems used and their own requirements (from the point of view of safety in particular).

In certain applications, it is for example desired that a breakdown of the compressed air distribution network leaves the installation in the state or it was at this precise moment so that the installation can restart in the same - conditions; in other applications, on the contrary, the aim is to return to a state of rest which allows the entire cycle to be carried out again during which the fault appeared.

 Finally, it appeared desirable to use components which could allow a later evolution of the installation, or a change in the nature of the signals or control means, without presenting themselves as different devices from those they replace or to which they are added, in order to maintain a uniformity of the installation facilitating its upkeep and maintenance by personnel accustomed to a certain presentation of the components.

 With this in mind, the invention intends to propose a pneumatic distributor, in particular of the 5/2 type (five channels, two positions), the constitution of which allows easy adaptation of the control signals of different nature, while retaining an identical general architecture whatever whatever the nature of the order, and of sufficiently low manufacturing cost so that the modernization or evolution of an existing installation is not felt by the user either as a major inconvenience or as an insurmountable economic obstacle.

Thus, more specifically, the subject of the invention is a pneumatic distributor comprising a substantially parallelepipedic body, having two large parallel faces for its sealed juxtaposition with at least one similar distributor, two lateral faces and two end faces in which are arranged.
- a bore perpendicular to the end faces to receive a control drawer,
- sections of supply and exhaust conduits perpendicular to the large faces and in communication with the bore,
- Connection orifices to a user device perpendicular to the lateral faces and opening onto one of them and in communication with the bore.

 According to one of the main characteristics of the invention, the means for controlling the position of the drawer are contained in plugs, which can be interchangeably coupled to the body, each having a single association face with one or the other. end faces of the body, projecting at least one cylindrical skirt, the external surface of which cooperates with the aforementioned bore and the internal surface of which constitutes a guide surface for a push-button of the drawer and determines with it a closed chamber of variable volume.

 This general characteristic consisting of a standard association face between a distributor body which remains unique and plugs which contain the means for adapting the distributor control to, in particular, the physical nature of this control, makes it possible to conserve to the distributor a unique general geometry despite the differences which may exist at the level of his order, and to easily change the order by adopting another plug which comes to be put in place in exactly the same way as that which has just been removed.

 In addition, as will be seen below, the adaptation means contained in the plugs can themselves be "standardized" so that one plug will be different from another only by relatively minor modifications of a or two standard basic blanks, one being for example intended for controlling the movement of the drawer, the other for returning the latter to its rest position. In a monostable dispenser two plugs each from a different blank will be used. In a bistable dispenser, two caps from a single blank will be used.

 Furthermore, the use of plugs all having the same face of association with the body allows a construction of the body such that the various communications ensured selectively between said sections and said orifices are established by the drawer of the distributor mounted to slide in the interior space of a stack of sealing rings and annular spacers, held axially in said bore by the annular skirts of the two opposite plugs.

 In addition, in order to rationalize as much as possible the manufacture of the different types of plugs that may be necessary, it will be advantageous to provide that each plug has a connection end piece, projecting from the association face, for an internal pipe with a bypass. of the supply duct section provided in the body and opening into each of said end faces.

 Thus, in a first mode of plug closure allowing the movement of the dispenser drawer to be controlled, the above-mentioned internal pipe of at least one of said plugs extends from the connection piece to the above-mentioned variable volume chamber in which it opens through its bottom wall, and is divided into two sections by a valve member, providing in a first position the free communication of the two sections and in a second position, the exhaust of the section coming from of the room and the interruption of the above communication.

 In a variant of this embodiment of the valve to be associated with a solenoid valve, said sections open into a recess open on the face of the stopper opposite its face of association with the body, in which said valve member is placed which is constituted by the valve of a solenoid valve coupled to the plug by said opposite face, said valve cooperating with a seat formed around the outlet in the recess of the section coming from the nozzle.

 In the case where the solenoid valve cooperates more conventionally with said sections, the latter open in the vicinity of one another on the face of the plug opposite its face of association with the body, while the solenoid valve is reported in a sealed manner on this face and ensures the aforementioned selective communications and interruptions between the two sections in a manner known per se, outside the plug.

 These two variants are suitable for electrical control of the dispenser by means of a solenoid valve.

 It is however possible to provide pneumatic control of the dispenser. In this case, the valve member placed in said recess is a permanent shutter of the pipe section coming from the end piece, formed in a pneumatic connection comprising, around this shutter, a channel, in permanent communication with the section coming from The pneumatic signal supply chamber from a separate distributor control source.

 In all your cases, it may be advantageous to provide a manual control by means of which one can simulate the existence of electrical or pneumatic signals for controlling the position of the dispenser drawer.

 To perform this function, the above-mentioned internal pipe has between said sections a direct sound link from the endpiece to the chamber, normally closed by a manually operable shutter towards a position for opening this link and concomitant closing of the section coming from. from the room.

 For the production of a monostable dispenser, that is to say in which the drawer is constantly subjected to a restoring force which tends to place it in a rest position, the internal pipe of the other plug extends between said nozzle and the aforementioned variable volume chamber and establishes a permanent communication between them, said chamber being of a smaller section than that of the chamber of the opposite plug.

 The drawer is then subjected to a pneumatic restoring force. In the case where the return force is exerted by a spring, the internal pipe is closed off permanently and tightly between the end piece and the chamber, the latter constituting a housing for an elastic member for returning the pusher which slides in the skirt .

 The invention will be better understood during the description given below by way of purely indicative and nonlimiting example which will make it possible to identify the advantages and the secondary characteristics thereof.

Reference will be made to the accompanying drawings in
Which
FIG. 1 is a simplified top view of a pneumatic installation using a multiplicity of distributors,
FIG. 2 is a sectional view of a distributor body through a transverse plane of FIG. 1, this body being equipped with two plugs to constitute a monostable distributor with spring return,
FIG. 3 is a sectional view of a variant of the plug delivering a pneumatic return force to give the dispenser a monostable character,
- Figure 4 shows in a sectional view, a plug variant for the execution of the displacement of the dispenser drawer using a solenoid valve different from this implementation in Figure 2
FIG. 5 is a partial section view of an alternative embodiment of a plug for controlling the movement of the drawer from a pneumatic signal,
FIG. 6 is a side view of a pneumatic installation using a reduced number of distributors,
- Figure 7 is a partial sectional view, on the plane VII-VII of Figure 6, of a distributor illustrating a particular connection of the latter to the pressure source and an embodiment of collected exhaust provided with a silencer .

 A pneumatic distribution system 1, visible in FIG. 1, comprises a multiplicity of unitary distributor bodies such as 2, which are associated against each other by their large face such as 2a, 2b and kept in tight relation by means of longitudinal compression forces provided by two blocking spacers 3 and 4 of the stack clamped by a pair of tie rods 5,6 which pass through aligned housings of each of the bodies. These spacers 3, 4 are in turn fixed using hooking means on the same profiled metal rail 7.

 Note in this figure that one of the spacers has two pneumatic connectors 8, 9, one of which is intended to supply the distributor bodies in parallel with a supply pressure, and the other 9, to collect their exhausts. Indeed, we see in Figure 2 which is a section along the line II-II of Figure 1, that each distributor body such as 10 has three sections of channels 11, 12, 13 of which one 11 is supplied with fluid under pressure, while the other two 12 and 13 collect exhaust fluids.

 Furthermore, each body 1 of generally parallelepiped shape has two lateral faces 14a, 14b.

Two orifices 15, 16 which are connected to a user device represented schematically and without limitation by the jack 17 open out from the body at one of the aforesaid faces 14a. It can be seen in FIG. 1 that the particular dispenser body 2 is equipped on its opposite end faces 2c, 2d with lateral plugs 18, 19 whose function and nature will be specified below.

In FIG. 2, it can be seen that the body 10 of the distributor 2 has a transverse bore 20 which extends
from the face 2c to the face 2d of the body 10. The two plugs 18, 19 comprise annular skirts 21, 22 projecting from the association faces 23, 24, which cooperate with the ends of the bore 20 when the faces 23 , 24 are pressed against the faces 2c and 2d and the plugs held on the body 10 by pins 25a, 25b, 26a, 26b. A stack of annular lip seals such as 27 and spacers such as 28 is freely mounted in this bore and kept tight
and in the axial position by the annular skirts 21, 22 engaged in the bore 20. Although this does not appear clearly from the drawings, it should be noted that the faces 23, 24 of the plugs are identical and are designed to be applied interchangeably on the end faces 2c and 2d of the body 10.

Coaxial with the bore 20, there is a slide valve 30 which has two grooves 31, 32 limited by three partitions 33, 34, 35.

 This drawer which is movable between a rest position and a working position, establishes or interrupts the circulation of a fluid between the channel sections 11, 12, 13 and the orifices 15, 16 by means of a sealed sliding of the outer surface of the partitions against the inner periphery of the joints; the spacers obviously have radial passages for the flow of the fluid. The plug 18, visible in FIG. 2, belongs to a first family of interchangeable functional plugs which is intended to communicate to the drawer 30 an elastic force of direction G, that is to say a restoring force.

 These plugs which are used to give a monostable character to the dispenser can use one or more concentric springs such as 36, 37. These are arranged in a cylindrical housing 38 which forms the internal volume of the skirt 21, are supported on the bottom 39 of this interior volume and exert a thrust which is transmitted to the end of the drawer by a pusher 40 guided in the housing 38 and which delimits in the latter a variable volume chamber. It is also noted that this chamber is connected to a pipe 41 circulating inside the plug 18 towards an end piece 42 for connecting this pipe 41 to a bypass 43 of the section of conduit 11 formed in the body 10. In the case of FIG. 2, a ball 44 permanently closes the pipe 41.

 The plug 19, also visible in FIG. 2, belongs to a second family of interchangeable functional plugs with plugs of the same family or plugs of the family described above, which is intended to communicate to the drawer 30 a displacement of direction F upon receipt of an order to change the status of the user device. To do this, the skirt 22 has a cylindrical inner surface, having substantially the same diameter as the housing 38 which forms a sliding surface for a small push piston 45 whose rod 46 is associated with the corresponding end of the drawer 30. The piston 45 delimits in the skirt 22 a chamber of variable volume 47.

This chamber 47, as in the case of the plug 18, is connected by an internal pipe to a nozzle 49 for connecting this pipe with a bypass 50 of the section of conduit 11 formed in the ccrps 10.

This internal pipe is, in the case of this plug 19, divided into two sections: a first from
the end piece 49 and referenced 51, 52 and 53 in FIG. 2 and a second section, 54, housing 55 and conduit 56 which terminates
at the bottom 48 of the chamber 47. The element for separating the internal pipe into these two sections is a valve element, which is shown in FIG. 2 in the form of a valve 57 cooperating with a seat 58 in the center of which leads to part 53 of the first section. The valve 57 evolves in a recess 59 open on the side of a face 60 of the stopper opposite that 23 of association with the body, which can receive a solenoid valve 61-controlling the position of the valve relative to the seat 58.

 It is clear that the valve 57 blocked on its seat 58 by the solenoid valve cuts the connection of the chamber 47 with the bypass 50 therefore the pressure source. The chamber 47 is then, by the second section, placed in communication with the exhaust 62 of the solenoid valve 61. In the other position of the valve, the first and second sections are in free communication and isolated from the exhaust 62.

 Note also in this figure the presence of a bypass between the nozzle 49 and the chamber 47 to short-circuit the valve member. This consists of the conduit 63 from the conduit 51 which terminates in your room 55 through a seat it is the same for the conduit 54, so that depending on the position of a valve 64 against one either of the seats, the chamber 47 is supplied directly or through the valve member. The valve 64 is operated by hand by an actuating pusher 65. The chamber 47 being at the exhaust by the solenoid valve, an order of change of state of the drawer 30 can be simulated by closing the channel 54 to open the communication between channel 56 and that 63 normally closed by the valve 64. By releasing this valve (or by raising it), the chamber 47 is allowed to be exhausted again.

The dispenser shown in this figure 2 is intended for applications where one wishes to see a monostable operating mode of the user device established.
such as cylinder 17.

 This operation is explained due to the existence of a permanent restoring force developed in direction G by the spring or springs 36, 37. When an order for change of state is sent in the form of an electrical signal to The solenoid valve 61, this moves its valve 57 in the direction of its separation from the seat 58. The pressure is therefore introduced by 51, 52, 53, 59, 54, 55 and 56 in the chamber 47 and thus causes a displacement of the drawer 30 in direction F, and a reversal of the pressures previously established at the orifices 15 and 16.

 The disappearance of the control signal on the solenoid valve establishes a purge of the chamber 47 through a reverse path 56, 55, 54, 59 to lead to the internal exhaust 62 of the solenoid valve 61. A verification of operation can be carried out temporarily, or more prolonged, by pressing the button 65, which causes the admission of pressure to the chamber 47 through the channels 63, 55 and 56.

 If one wishes to give the distributor a bistable operating mode, the plug 18 is replaced by a second plug such as 19 while associating the electrical circuits supplying the two solenoid valves with a locking device to prevent simultaneous excitation of their coils. .

 The stability of the position of the balanced drawer in the opposite extreme positions of rest and work, can be imparted by the friction which is exerted on its partitions by the lip sealing rings 27; it is therefore not necessary to establish a permanent excitation of one or the other of the solenoid valves, short duration pulses being sufficient to operate the desired switches.

 Another type of plug belonging to the plug family 18, that is to say used in the case of monostable distributors, is shown in FIG. 3. It has a plug body 68 identical to that of the plug 18.

 However, in the internal housing of the skirt 21, a waterproof jacket 69 has been placed inside which a small piston 70 slides.

 The latter, which has a diameter - d less than the diameter of the piston 45 of FIG. 2, comes into contact with the end of the slide 30 to provide it with a constant restoring force in direction G, when a permanent pressure is applied in the variable volume chamber 71 between the piston 70 and the bottom 39 of the chamber 69.

This pressure is here that which prevails in the network or the channels 11 and which is transmitted by the connection end piece 42 being, in this case, devoid of sealing ball.

 It will be recalled that the nozzle 41 penetrates in a sealed manner in a c-wave 43 of the body 10 of the dispenser where permanent pressure is exerted. The monostable operation is identical to that described above, while presenting, here, a state memory property; when the pressure disappears on the entire distributor, the piston 70 indeed retains the position which was hers before this disappearance due to the friction developed between it and the jacket 69. With this plug 68, a restoring force is therefore developed elastic and pneumatic providing a memory effect.

 FIG. 4 illustrates a plug comparable to that 19 of FIG. 2.

 The main difference here lies in the fact that this plug is designed to receive a small solenoid valve 72 in the body of which are already disposed, in addition to the electromagnet 73, a valve 74 which can be moved between two seats, the one 75 is supplied with permanent pressure through a channel 76, while the other 77 is connected to the exhaust 78. A chamber 79, in which the valve moves, is in turn connected to an outlet orifice 80.

 We find in the cap of Figure 4, the main channels with the same references as in Figure 2.

However, instead of opening into a recess, the conduits 53 and 54 open side by side on a face 60 ′ of the plug opposite its face for association with the body 10 and adapted to receive the solenoid valve 72 so that the channels 76 and 80 are in correspondence with the channels 53 and 54. The selective switches are then made in the solenoid valve 72 in the usual manner. The versatile nature of the dispenser which has just been described can be further improved to make it universal, by using means to give the plugs of the transmission type of control signals, drawer control information appearing directly under the form of pneumatic signals.

 This enlargement in the nature of the control means which can be accommodated is obtained by means of a particular pneumatic connector 90 visible in FIG. 5, where it is noted that the recess 59 of the plug 19 comprises a socket 91 internally threaded and fixed to using annular studs such as 92 in said recess where the channel 53 opens.

 This connector 90 comprises a threaded end piece 93 which engages in the tapping of the socket 91 where it is held in a watertight manner by means of the seal 94. A fixed central valve 95 comes to bear against the seat 58 to close the channel pressure 53 which passes through it, while an internal pipe 96 starts from a connection ring 97 capable of receiving a flexible pipe 98 to end at its opposite end in small channels 99, 100 communicating with the recess 59.

 The implementation of this connector makes it possible to communicate pneumatic control orders by connecting the pipe 98 to a signal source which will communicate its pressure by the same section of internal pipe 54 of the plug as that which is followed by the controlled control fluid. electro-pneumatic loss from recess 59 (Figure 2).

 To respond to a concern for simplification which occurs when only one or a reduced number of distributors is used, it is possible to dispense with the use of spacers such as 5, 6, see FIG. 1, and replace this by with simple metal plates 101, 102, see FIG. 6, which are provided with sealing means for longitudinally closing off the portions of channels 11, 12, 13 and fixing lugs 103, 104. The bodies 10 of the distributors then receive sockets 105 , 106, 107 communicating with the channel portions 11, 12, 13, see FIG. 7. These sockets are put in place of the closure capsules A, B, C of perpendicular branches, provided in each body 10, on its lateral face 14b, and are tightly fixed in cylindrical housings such as 108, and which receive, for example, a pneumatic connector such as 109 transmitting the supply pressure, as well as two silencers 110 which dampen the fluids of exhaust .

 This arrangement naturally implies that the plate 111 supporting the plates 101, 102 is provided with an opening 112 to allow the passage of these silencers and a supply pipe.

 The invention finds an interesting application in the field of pneumatic equipment for machines.

Claims (11)

 1. Pneumatic distributor comprising a body (10) substantially parallelepipedic, having two large parallel faces (2a, 2b) for its sealed juxtaposition with at least one similar distributor, two lateral faces (14a, 14b) and two end faces (2c , 2d) in which are housed  - a bore (20) perpendicular to the end faces (2c, 2d) to receive a control slide (30);  - sections (11, 12, 13) of supply and exhaust conduits perpendicular to the large faces (2a, 2b) and in communication with the bore (20);  - orifices (15,16) for connection to a user device perpendicular to the lateral faces (14a, 14b) opening onto one (1 4a) of them, and in communication with the bore (20), characterized in that that the means for controlling the position of the drawer are contained in plugs (18, 19), which can be coupled to the body (10) interchangeably, each having a face (23, 24) of single association with one or the other 'other of the end faces (2c, 2d) of the body (10), provided projecting at least one cylindrical skirt (21, 22) whose outer surface cooperates with the bore (20) above and whose surface interior constitutes a guide surface for a pusher (40,45) of the drawer (30) and determines with it a closed chamber (38,47) of variable volume.  2. Distributor according to claim 1 characterized in that the various communications provided selectively between said sections (11, 12, 13) and said orifices (15, 16) are established by the drawer (30) of the distributor mounted to slide in the interior space of a stack of sealing rings (28) and annular spacers (27), held axially in said bore (20) by the annular skirts (21,22) of the two opposite plugs (18, 19).  3. Distributor according to claim 1 or claim 2, characterized in that each plug (18,19) comprises a connection end piece (42,49) projecting from the association face (24,23) for an internal pipe. (41,51) with a bypass (43, 50) of the section (11) of supply conduit provided in the body and opening into each of said end faces (2c, 2d).  4. Distributor according to claim 3 characterized in that the internal pipe (51,52,53,54,55,56) of said at least one of said plugs (19) extends from the nozzle (49) connection to the chamber (47) of said variable volume in which it opens out through its bottom wall (48) and is divided into two sections (51, 52, 53; 54, 55, 56) by a valve member ( 57), realizing in a first position the free communication of the two sections and in a second position the exhausting of the section (54, 55, 56) coming from the chamber (47) and cutting off the above communication.  5. Distributor according to claim 4 characterized in that said sections (51,52,53) (54,55,56) open into a recess (59) open on the face (60) of the plug (19) opposite its face association (23) with the body (10), in which is placed said valve member (57) which is constituted by the valve of a solenoid valve (61) coupled to the plug by said opposite face (60), said valve cooperating with a seat (58) formed around the outlet in the recess of the section (53) coming from the end piece.  6. Distributor according to claim 4 characterized in that said sections (51-53) (54-56) open in the vicinity of one another on the face (60 ') of the plug (19) opposite its face ( 23) of association with the body, while a solenoid valve (72) is attached in a sealed manner on this face and ensures the aforementioned selective communications and interruptions between the two sections in a manner known per se, outside the plug (19).  7. A dispenser according to claim 5 characterized in that the valve member placed in said recess is a shutter (95) permanent section of the pipe from the tip, formed in a pneumatic connector (90) comprising, around this shutter, a channel (99, 100) in permanent communication with the section (54) coming from the chamber, for supplying pneumatic signals coming from a separate source for controlling the distributor.  8. Distributor according to any one of claims 4 to 7, characterized in that the above-mentioned internal pipe (51-56) has between said sections a bypass (63) for direct connection of the end piece (49) to the chamber (47) normally closed by a shutter (64) which can be operated manually towards an opening position of this bypass and concomitant closing of the section (54, 55, 56) coming from the chamber (47)  9. A dispenser according to claim 3 characterized in that the internal pipe (41) of the other plug extends between said nozzle (42) and the above-mentioned variable volume chamber (38) and establishes permanent communication between them, said chamber being of a smaller section than that of the chamber of the opposite plug.  10. A dispenser according to claim 3 characterized in that the internal pipe (41) is permanently closed and sealed between the end piece (42) and the chamber (38), the latter constituting a housing for an elastic member ( 36, 37) for recalling the pusher (40) which slides in the skirt (21).  11. Distributor according to any one of the preceding claims, characterized in that the sections of ducts (11,12,13) supply and exhaust have branches perpendicular to the side face (14b) of the body (10) opposite to that (14a) provided with the aforementioned connection orifices (15,16), which open on this face and which are normally closed by removable capsules (A, B, C) -