Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
  • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
  • F15B13/00—Details of servomotor systems ; Valves for servomotor systems
  • F15B13/02—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors
  • F15B13/04—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors for use with a single servomotor
  • F15B13/0401—Valve members; Fluid interconnections therefor
  • F15B13/0402—Valve members; Fluid interconnections therefor for linearly sliding valves, e.g. spool valves
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T137/00—Fluid handling
  • Y10T137/8593—Systems
  • Y10T137/86493—Multi-way valve unit
  • Y10T137/86574—Supply and exhaust
  • Y10T137/8667—Reciprocating valve
  • Y10T137/86694—Piston valve
  • Y10T137/86702—With internal flow passage
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T137/00—Fluid handling
  • Y10T137/8593—Systems
  • Y10T137/86493—Multi-way valve unit
  • Y10T137/86574—Supply and exhaust
  • Y10T137/8667—Reciprocating valve
  • Y10T137/86694—Piston valve
  • Y10T137/8671—With annular passage [e.g., spool]

Definitions

• the invention relates to a control valve for a hydraulic motor according to the preamble of claim 1.
• Hydromotors are used, for example, in cranes for driving hydraulic winches. With such a winch, loads can be lifted and lowered.
• a hydraulic directional control valve which allows a load pressure independent control of a hydraulic motor.
• DE-C2-41 36 991 a directional valve is known, which can be used for the same purpose.
• the invention has for its object to provide a control valve which prevents the previously described torque fluctuations and pulsations without the need for an additional valve assembly, which was previously used to reduce the pulsation or torque fluctuation.
• 1 shows a diagram of a control for a hydraulic motor
• 2 shows a valve assembly as an additional unit for the function "lifting" according to a solution according to the prior art
• Fig. 3. is a view of a spool within a valve body
• Fig. 4 to 7 sections of the position of the spool relative to a control edge.
• a hydraulic motor 1 which drives a not shown in detail winch for lifting and lowering a load 2.
• Arrows on the hydraulic motor 1 is shown that the one direction of rotation of the hydraulic motor 1 causes the lowering of the load 2, the opposite direction of rotation of the hydraulic motor 1, the lifting of the load.
• the hydraulic motor 1 is controllable by a control valve 3 designed as a directional control valve with the usual load connections A and B and with a pump connection P and a tank connection T. This corresponds to the known prior art. This also applies to an inserted into the supply line to the hydraulic motor 1 load-holding valve 4, which serves to control the load during lowering.
• a hydraulic motor 1 comes in such applications preferably a Hubverdrängermaschine used, for example, an axial piston machine, as shown in "Dubbel: Taschenbuch for mechanical engineering", Springer-Verlag, 19th edition, on page H5.
• this widespread type of machine has the disadvantage that the flow is not uniform, because this has a considerable degree of non-uniformity ⁇ . It may even follow that at the beginning of the Lifting the load 2, so at very low speed of the hydraulic motor 1, the load 2 drops briefly. This also applies when reducing the speed to stop the load 2. A rational work is hardly possible and there are dangerous moments.
• valve assembly 10 for example, in the corresponding return line from the hydraulic motor 1, as shown in FIG.
• the B-line valve assembly 10 which consists of two mutually parallel check valves, namely a biased check valve 11 and a non-biased check valve 12.
• the applicant itself has created in 2001 such a valve assembly.
• the hydraulic oil flowing from the hydraulic motor 1 to the control valve 3 must pass through the valve assembly 10.
• a solution with such an additional valve assembly 10 is complicated to manufacture and expensive and requires space. But the invention is also particularly the object of improving such a solution in terms of functionality.
• Fig. 3 is a view of a spool 20 is shown within a valve body 21, which are the control valve 3 associated.
• the spool 20 is axially displaceable, which is indicated by a double arrow.
• the axial displaceability is effected, as usual in such proportionally operating control valves, by means of at least one drive, wherein electrical, hydraulic or pneumatic drives find uses. Since in the present case, the number and type of drive for the spool 20 does not matter, such a drive has not been shown in the figure.
• transverse bores are present in the valve body 21, which lead up to the longitudinal bore 22.
• each of the working connection bores A, B must be operationally connectable to the tank connection bore T or to the pump connection bore P in order to enable "lifting" and "sinking" operation.
• the spool 20 has, in order to produce the various connections between the terminal bores T, B, P, A and T, profiled annular grooves. Seen from the left, these are a B-tank groove 23, a B-control groove 24, a pump groove 25, an A-control groove 26 and an A-tank groove 27.
• the principle is common to most directional control valves.
• the relative position of the spool 20 in the longitudinal bore 22 is in the illustration in Fig. 3 so that the pump port hole P is completed, so that there is no connection to one of the adjacent working port holes A, B. It follows that the hydraulic motor 1 stands still because no hydraulic oil is supplied to it. Shown is the zero or neutral position.
• the control valve 3 shown here for a hydraulic motor 1 now has an additional narrow auxiliary control groove 28, which is arranged between the B-tank groove 23 and the B-control groove 24.
• auxiliary control groove 28 At the bottom of this Hilfs marsnut 28 begins a first transverse bore 29 which opens into a longitudinal bore 30, the other end is in communication with a second transverse bore 31.
• This second transverse bore 31 establishes a connection to the B-tank groove 23 and thus to the tank connection bore T.
• a biased check valve 32 is arranged with a biasing spring 33, in such a way that it is to be opened by a higher pressure from the working port bore B ago.
• the control edge for controlling the volumetric flow between the working connection bore B and the second tank connection bore T is designed in a particularly advantageous manner.
• the spool 20 On both sides of the auxiliary control groove 28, the spool 20 has short cylindrical sections, namely to the right of a sealing cylinder 35 and left thereof sinen biasing cylinder 36. To the left are two frusto-conical sections, namely a first control taper portion 37 with a weaker surface inclination and then a second control cone section 38 with a stronger surface inclination.
• FIGS. 4 to 7 an identical section of the control valve 3 is shown, which is shown in FIG. 3 with a dotted circle.
• the aim is to show how the object of the invention is achieved with the inventive and the advantageous means.
• FIG. 4 shows that a control edge 40 assigned to the working connection bore B lies in the region of the sealing cylinder 35.
• the working connection bore B and the tank connection bore T (FIG. 3) located farther to the left.
• the auxiliary control groove 28 is covered with the transverse bore 29 beginning therein from the control edge 40, the pressure prevailing in the working port bore B does not act in the transverse bore 29 into it.
• This state is given when, as shown in Fig. 3, the connection of the pump port hole P is shut off both to the working port hole A and only working port bore B, so that the hydraulic motor 1 (Fig. 1) is stationary. Again, the zero or neutral position is shown.
• the hydraulic motor 1 is hydraulically biased, with the result that the uneven startup at low speed is greatly improved in a very simple manner. Accordingly, the degree of non-uniformity ⁇ can not practically work as a non-uniform rotational movement during slow starting. Incidentally, this also applies to the slow speed after a delay from faster running.
• Fig. 6 the state is shown in still further control of the control valve 3 in the "lifting" mode.
• the control edge 40 by the relative to FIG. 5 further movement of the spool 20 to the right so that the first control taper portion 37 with the weaker surface inclination is right of the control edge 40.
• hydraulic oil can now flow between the control edge 40 and the first control cone portion 37.
• the hydraulic oil flowing back from the hydraulic motor 1 (FIG. 1) to the tank flows through both the check valve 32 (FIG. 3) and the ring cross section between the control edge 40 and the control cam portion 37.
• control piston 20 is moved to the right, the greater the flow of hydraulic oil between the control edge 40 and control cone portion 37th That the check valve 32 does not close immediately when the control edge 40 comes into the region of the first control taper portion 37, is because that due to the flow between the control edge 40 and the control cone section 37, an equally high dynamic pressure is created as over the prestressed check valve 32.
• the biasing spring 33 is dimensioned so that the resulting return bias is about 25 bar.
• the surface inclination of the first control cone section 37 is dimensioned approximately such that the angle to the imaginary cylindrical surface of the control spool 20 is approximately 16 °.
• the surface inclination of the second control cone portion 38 is advantageously about 26 °. The dimensions otherwise depend on the size of the control valve 3, ie of its maximum flow. But then it does not require any inventive step to optimize this measure.
• the invention is always applicable when loads are to be lifted in devices with a hydraulic motor.

Landscapes

• Engineering & Computer Science (AREA)
• Physics & Mathematics (AREA)
• Fluid Mechanics (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Fluid-Pressure Circuits (AREA)
• Servomotors (AREA)
• Check Valves (AREA)
• Multiple-Way Valves (AREA)
• Valve Device For Special Equipments (AREA)
• Magnetically Actuated Valves (AREA)
• Valve-Gear Or Valve Arrangements (AREA)

Applications Claiming Priority (2)

Publications (2)

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Family Applications (1)

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• 2005
  • 2005-12-01 DE DE200550004981 patent/DE502005004981D1/de not_active Expired - Lifetime
  • 2005-12-01 US US11/918,688 patent/US7921879B2/en not_active Expired - Fee Related
  • 2005-12-01 WO PCT/CH2005/000717 patent/WO2006111031A1/fr not_active Ceased
  • 2005-12-01 AT AT05804312T patent/ATE403807T1/de not_active IP Right Cessation
  • 2005-12-01 EP EP05804312A patent/EP1872018B1/fr not_active Expired - Lifetime
  • 2005-12-01 JP JP2008506896A patent/JP2008537069A/ja active Pending

Non-Patent Citations (1)

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