FR2577002A1 - DISTRIBUTOR DRAWER WITH INCORPORATED BALANCING VALVE FOR HYDRAULIC CIRCUITS - Google Patents

Abstract

THE INVENTION CONCERNS THE DRAWER OF A HYDRAULIC DISTRIBUTOR. THE TWO HALF DRAWERS 121 AND 122 SLIDE ON THE TENSION ROD 113 TO CONSTITUTE THE MOBILE CREW IN THE STATOR 101. THE BALANCE BETWEEN THE SUPPLY PRESSURE AT 103 ACTING ON THE INTERSTICE125 AND THE ANTAGONIST THRUST OF THE SPRINGS 135, 139 DEFINES THE EQUILIBRIUM POSITION OF EACH OF THE HALF DRAWERS121, 123 ON THE TENSION ROD113. APPLICATION: THE BALANCING OR BRAKING VALVE IS THUS INCORPORATED IN THE DRAWER.

Description

The present invention relates to a dispenser drawer of a type

  new, equipped with a balancing valve incorporated, in particular to ensure the control or switching on hydraulic circuits. Generally, these balancing valves are distinct from the actual distributor to which they must be connected by pipes whose length is involved in the operating characteristics of the valve.

  circuit. This results in various disadvantages of

installation and maintenance.

  The present invention aims to

  avoid these disadvantages. by making a drawer of dis-

  a hydraulic tributor which is directly incorporated a balancing valve. More particularly, although not exclusively, the present invention aims at equipping a proportional hydraulic distributor of the type described in the French patent application 84 06 747, filed on April 18, 1984, in the name of the present Applicant, under the title: 'Hydraulic distributor of the proportional type

  with information about the strongest pressures

  in the circuits of use ".

A dispenser device according to

  the invention comprises a distributor valve with grooves

  smoothing in a stator bore along which are

  parts of the distribution, supply and return lights, and is characterized in that the drawer is made by assembling at least three moving parts relative to each other, namely:

  - a longitudinal assembly tie rod whose central body

tral is cylindrical

  - two half-drawers provided? each of a longitudinal bore

  internal tudinal and external grooves, these two half-drawers being slidably mounted one in the extension of the other. on the cylindrical body of the

  pulling which runs through their longitudinal bores.

According to another characteristic

  of the invention the opposite ends of the two half

  Each of them includes each. a flared support flange

  to receive the thrust of a coil spring of compres-

  sion also bearing on the stator.

  According to another characteristic of the invention. the tie rod has. at each of the two ends of its cylindrical body, a shoulder capable of receiving at the beginning the flared end

  of the half-drawer corresponding to more than this thickness.

  LEMENT. a cylindrical section whose end is

  to define a second shoulder of greater diameter.

  and whose outer diameter is substantially equal to that of the corresponding flared end of the half-slide, a second compression coil being disposed

  between the two flared flanges, that of the tie rod and

  the end of the half-drawer According to another feature of the invention, the end diameters of each half-drawer,

  and the taring of the first and second springs

  are defined in such a way that this half-drawer

  glue its abutment shoulder to the corresponding end.

  only when the pressure in the stator light corresponding to the power supply of a receiving apparatus falls below a predetermined threshold. This corresponds in particular to the case where the receiving apparatus has a motor operation (for example, a holding cylinder driven by the weight of the load it handles), in which case the relative movements of the half-drawer or

  function as a di-equilibrium valve

  braking or braking, incorporated in the drawer.

  The appended drawing, given as a non-restrictive example, will provide a better understanding of the

features of the invention.

Figure 1 is a sectional view

  of a device according to the invention in position

rest.

Figure 2 shows the same device

  in operation, when the load to be moved is received

  trice, that is to say when it opposes a resistance to the hydraulic receiver device Figure 3 shows the device in operation, when the load to move is driving, that is to say when it tends for example by his own

  weight, to drive the hydraulic receiver.

  The apparatus shown in the drawings is provided, for example, to replace the mounted drawer 3

  in the stator 1 in the French patent application

  As in this case, the stator 101 according to the invention comprises a bore 102, along which are distributed several distribution lights, namely: a central lumen 103 connected by a duct 104 to

  a source of hydraulic power supplying fluid

pressurized

  two grooves or distributor lights 105 and 106

  linked by pipes 107 and 108, to a hydraulic receiving apparatus (for example to each of the two chambers of a double-acting cylinder) - return lights 109 and 110, connected to the return circuit: - lights 111 and 112 , provided at both ends and connected, both in the known manner, to a common pipe for the detection of pressure

  of use (in English: "load sensing").

  Inside the 102 bore

  smooth a drawer that. according to the invention, is formed by

  appearance of the following three elements: - an assembly tie 113, provided with a central portion or cylindrical body 114, whose ends sontreliés

  by two shoulders 115 and 116 'to cylindrical sections

  ends 117 and 118 which each end with a flared support flange 19, 120

  two half-drawers 121 and 122 each having a tufted shape

  whose cylindrical central bore 123, 124,

  smooth along the cylindrical body t14 -

  When the two half-drawers 121 and 122 are in abutment in the rest position, each against his

  shoulder 115 116 (Figure 1). their ends in

  gard define between them a gap 125-, in which l? The supply pressure of the o04 channel can be exerted on each of these extremes in regain 12 127 wj On the py zJ. In the known manner, the external latch of the half-drawer 121 is machined with distribution notches 128, 129 which move in the face of the various stator lights 105 109, 111.

  dispensing notches 130, 131 are machined on the

  Rectangular half-spool box 122 Around the half-drawer 121, compressed

  between its flared back flange 132 and the stator wall

  than the corresponding one, a first spring is provided

  134. Behind the flange 132, take

  and a second helical spring 135, compressed

  in addition against the rear flange 119 of the tie 113.

  This spring 135 is arranged around the cylindrical section -

  117. At the other end of the dispenser, a similar arrangement is provided, where a first spring 136 is compressed between a flared rear flange 137 of the

  half-drawer 122 and the corresponding statoric transverse face

  138. A second coil spring 139, disposed around the cylindrical section 118 is compressed against the rear face of the collar 137 Each of the two ends of the movable element 113, 121, 122 is capped by a sealed bell 140 to 141. provided of an orifice 142, 143, which receives the piloting pressure of the apparatus The operation is as follows: When 1 set is at rest it occupies the neutral position illustrated in FIG. 1 as defined by 1 When the user sends the control pressure into aperture 143 to move a receiving load (i.e. the displacement of which resists resistance) the hydraulic power source (light 103) is pressure. The pilot pressure having pushed the mobile unit 113 121 - 122 towards the

  left the pressure of the light 103 is sent by the

  In addition, the pressure in the opening 103 is exerted between the two half-drawers 121 and 122 at the gap 125 which separates their opposite ends. Because of the resulting thrust, each of the two half-drawers 121 and 122 remains in abutment against its rear shoulder 115, 116, of the pull-rod 113 In this configuration, the springs 135 and 139 are pre-stressed. The power and return functions are

  synchronized in the known manner.

  If, on the contrary, the load to move is driving (for example if, by its own weight, it tends

  to accelerate its movement of movement), when the use

  the user sends the pilot pressure in the opening

  143, the device occupies the position illustrated on the

  In this case, the half-drawer 122 and the tie rod 113 move, as before, to the left, but

  this time, because of the motive of the charge, the pressure

  in the light 103 may be weak or even zero.

  under these conditions, when this pressure decreases, it crosses the prestressing threshold from which the effect of the spring 135 becomes preponderant compared to the thrust that the pressure in the light 103 exerts (from right to left in the figure 3), on the end of the half-drawer 121 corresponding to the gap 125, which is therefore reduced, and possibly canceled, as in the case of Figure 3. The half-drawer 121 is therefore closer to or less the demitiroir 122, and this relative movement has the effect of reducing the passage section between the dispensing light 105, and the return channel 109 This results in a self-adjusting étangglement effect by the

  notches 129, which inhibits the return to the reservoir of the receiver.

  and generates, in the receiving apparatus, a pressure which creates the load or the braking torque on the load When the braking force is sufficient, the light 103 which always receives the feed rate of the receiver is stabilized at the pressure value which defines the right opening of the return notches 129, that is to say the desired value for the amplitude of the gap 125

  Of course, one would not leave the home

  of the invention, by modifying the practical realization

  positioning or booster devices for movements

  longitudinal elements of the moving element 113, 121, 122 In particular, the two springs 135 and 139 could

  be replaced by a single spring at one end.

Claims (4)

  1 - Dispensing device comprising a slide valve distributor sliding in a stator bore (102), along which distribution lights (107) (108) are distributed. supply (103) and return (109) (110) characterized in that the drawer is made by assembling at least three moving parts relative to each other, namely: - a longitudinal assembly tie rod (113) whose central body (114) is cylindrical   - two half-drawers (121) (122), each provided with an   inner longitudinal wisdom (123). (124) and.d.'encQ-hes   128 (129) c (130), - (131), these two half-   rors (121), (122) being slidably mounted. Mon   in the extension of the other on the cylindrical body--   (114) of the tie rod (113) passing through their longitudinal bores (123). (124)   2 - Dispenser device according to the   1. characterized in that the opposite ends of the two demitiroirs (121) (122). each comprise a flared support flange (132) (137) for receiving the thrust of a first compression coil spring (134) (136) which also bears on the stator - (101).   3 - Dispenser device according to the re--   claim 2, characterized in that the tie rod of   ge (113) comprises at each of the two ends of its cylindrical body (114), a transverse shoulder (115), (116) capable of receiving - abutting the bearing flange (132). corresponding drawer (121) (122) then, beyond this shoulder (115), (116), a cylindrical section (117) (118) whose end is flared to define a second flange (119), ( 120)., More   large diameter, and whose outer diameter is sensi-   equal to that of the corresponding flared collar   (132), (137) of the half-drawer (121u, {! 22), a second res-   helicoidal compression fate (135) X (139) being   s between flared flared daxes (132) o (119) and (137) g- (920i). the pulling (113) and that of the end da half-drawer (121), (122).   4 - Dispenser device according to one   any of the preceding claims, characterized in that   the diameters of the ends facing each half-drawer (121), (122) ((gap (125)) and the setting of the first (134) (136) and the second (135) (139) springs corresponding thereto are defined so that this half-slide (121), (122): does not take off from its abutment shoulder (115) (116) on the corresponding end of the tie rod (113), that   when the pressure in the stator light (103) cor-   responding to the power supply of a receiver device falls   below a predetermined threshold which corresponds in particular to   in the event that the receiving apparatus is moderately   the relative displacements of the half-drawers (121), (122) ensure the operation in the manner of a balancing or braking valve, incorporated in the drawer