FR2520816A1 - INTERCALING DEVICE IN A HYDRAULIC CIRCUIT AND COMPRISING A SAFETY SWITCH - Google Patents

Abstract

THE INVENTION RELATES TO HYDRAULIC CONTROL EQUIPMENT. THIS DEVICE INCLUDES A SAFETY SWITCH 1 INTERCALED IN A HYDRAULIC CIRCUIT, THIS SWITCH INCLUDING A ROTATING DISTRIBUTION VALVE INTEGRATED INTO THE CONSTRUCTION IN THE CASING OF A PILOT CONTROL UNIT 2, WHICH IS EQUIPPED WITH A WORKING FLUID DUCT THE LINE 5 OF THE PILOT PUMP CAN BE CONNECTED TO THE LINE 12 RETURN TO THE TANK. MAIN APPLICATION: PROTECTION AGAINST ACCIDENTAL FALSE OPERATIONS OF HYDRAULIC EQUIPMENT, FOR EXAMPLE IN PUBLIC WORKS VEHICLES AND EQUIVALENT MACHINES.

Description

The invention relates to a device

  in a hydraulic circuit and having a switch

  Here, the liquid represents a working fluid.

  lant whose transmission to a receiving device can be established or interrupted In installations of this kind, the hydraulic circuit distributor

  is controlled by a pilot control device

  interposed in a hydraulic control circuit.

  The purpose of the invention is to guarantee that

  there will be no involuntary control maneuver.

  There is a particular risk of involuntary maneuvering

  where, because of the restricted space, the

  are likely to be manipulated by the con-

  driver of the machine that touches them involuntarily

  this can easily happen, for example, in the case of public works machinery equipped with a narrow cabin,

  when the driver gets into or out of the cabin.

  According to the invention, this problem is solved in a device of the type described at the beginning of this memo

  in that the device comprises a dispensing valve

  revolving tribution, integrated with the construction in the car-

  of a pilot control apparatus, which is provided with a working fluid conduit through which the conduct of the

  pilot pump can be connected to the driving

tower to the tank.

  The advantage of the invention is that

  the safety switch, being incorporated in the car-

  of a pilot control device, does not require

  additional hydraulic draws, does not require

  this special and may already be put in a state of

  with little work, at the time of

  the pilot control unit.

  To improve security, the switch

  safety is mounted on the flow path of the fluid

  between the inlet of the pump discharge

  pilot and the other fluid channels working from the

same as pilot control.

  The figures of the appended drawing, given by way of non-limiting example, will make it clear how the invention can be made.

  FIGS. 1 and 2 represent the hybrid circuits

  working hydraulics and FIGS. 3 and 4 illustrate the functions of the safety switch activated in the case where the apparatus

  driver can not transmit any order.

  Figure 1 shows the safety switch 1 incorporated in the casing of the pilot control apparatus

  2 Here, the safety switch is arranged on the

  fluid circulation jet of the fuel control circuit

  fluid working from the tank 3 and put under the working pressure by the pilot pump 4,

  such that it is interposed between the entrance of the re-

  pilot pump flow and the other working fluid channels of the pilot control unit 2 If the safety switch 1 is in the inactive position of its working fluid conduit, position

  shown in FIG. 1, the working fluid is

  flows into the control circuit, passing through the

  5 of the control pump, the inlet duct 6, the control path 7 and the transmission duct 8 of

  the piloted project, leading to the distributor of

  vail 9; from there, the fluid flows through the line of

  110 control led by the conduit 11 back to the tank and from there it finally returns to the tank 3

  by the pipe 12 back to the tank In a way con-

  naked in itself, the necessary condition for the realization of this pilot hydraulic fluid flow is a suitable control position of the control lever 13

  and, therefore, a certain position of the piston of com-

  in the control path 7 This leads to a chosen switching position of the working distributor

  9 and, as a result, to a labor maneuver in the

  baked work of the hydraulic installation, which circuit is represented by a working pump 14 and a device

receiver 15.

  FIG. 2 shows a section of the safety switch 1 taken along the section line A-B of the safety control lever 16. It is clearly seen in this figure the rotary distribution valve 17 integrated in the casing of the pilot control unit 2 and

  which has a working fluid duct 18 which, se-

  In the angular position of the rotary valve 17, either transmits the working pressure in the inlet channel 6, as shown in FIG. 2, or connects the discharge pipe 5 of the pilot pump to the pipe 12.

  back to the reservoir, according to the representation of the

Figure 4.

  FIG. 3 shows another angular position of the safety control lever 16, in which the working fluid conduit of the safety switch

  is traversed by the fluid and where, consequently, the

  very fluid channels working from the

  pilot are short-circuited.

  the control lever 13 has no effect on the

  circuit of the working hydraulic fluid nor on the

15.

  Figure 4 shows a sectional view of the

  safety, taken along line C-D of the

  re 3 and represents this switch in detail The new PO sition of the rotary valve 17 establishes a short circuit

  fluid flow working to send it back direc-

  of the discharge pipe of the pumping pump.

  batching at the pipe 12 back to the tank.

  It goes without saying that modifications may be made to the embodiment just described,

  in particular by substituting equivalent technical means

  slow, without departing from the scope of the invention.

Claims (2)

  1 Device comprising a selector switch   characterized in that the device comprises a rotary distribution valve (17), integrated with the construction in the casing of a pilot control apparatus (2), which is provided with a fluid duct working (18) by which the pipe (5) of the driving pump can be connected to the   pipe (12) back to the tank.   2 Device according to claim 1,   characterized in that the safety switch (1) is   mounted on the flow path of the fluid   the discharge inlet of the pilot pump and the other working fluid channels of the pilot control (2).