DE2417161A1 - SELF-COMPENSATING VALVE DEVICE - Google Patents

Description

Augsburg, April 3, 197'i

AUSTRALIAN IRON & STEEL PTY. LIMITED

Hoska Kembla Works

Port Kembla, New South Wales

Australia

Self-compensating valve device.

The invention relates to a self-compensating valve device for controlling a plurality of liquid-operated ones Devices with regard to their primary fluid requirements.

The invention described below can be used in almost all situations where a number individual, but mutually assigned liquid-operated devices are to be operated on a single supply source for high-pressure liquid. However, in this description, for the sake of simplicity, it is used in conjunction with a rock or Ceiling drill attached to a mining machine

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can be described.

The invention is characterized in that it comprises

a large number of selective control valves of the piston (spool, "spool" - *) type,

a primary current divider that has a Supply liquid in two volumetrically different Flow paths separates the first one , a first selective control valve is directed, ' that optionally, depending on the requirements, the liquid on one of three liquid lines to one first liquid-powered device distributed during the second flow path is directed to the remaining selective control valves and optionally through one or more liquid lines to a multitude of additional, individual, liquid-operated ones Devices for whose function control are distributed depending on the requirements,

a pressure responsive device that provides a flow of liquid to one of the additional Gauges devices when the pressure of the liquid to the first device rises above a predetermined value,

a device with which the flow of liquid to said, an additional device is reversed is when this device reaches a maximum position »

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The invention is described below with reference to the drawing using exemplary embodiments explained in more detail; show it

Fig, 1 schematically shows the flow circuit of a

Valve device according to the invention;

Fig. 2 is a longitudinal section of an automatic variable orifice device which is used in the flow circuit of Figure 1 and provides two stage flow from the primary flow divider;

Fig. 3 is a longitudinal section through a control valve, which in the flow circuit of Fig.l is used;

4 shows a longitudinal section through an anti-stop valve, which is incorporated in the control valve of Fig. 3;

5 shows a schematic flow circuit,

which is similar to the flow circuit of FIG. 1, but with an additional control unit and contains an additional liquid-operated device.

The valve device shown in the drawings comprises a primary flow divider 5 and valves 6, 7 and 8. Fig. 1 shows how these valves are used, so that the devices such as engines 9 and 10 and cylinder 11] Liquid power is supplied.

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A flow of liquid of, for example, about 90 l / min (20 gallons / min) entering the flow divider 5 (Fig.l) is fed, is divided into two separate flow paths 12 and I3. this is reached through opening 4. (Fig. 1) which has a flow of approximately 13 l / min (3 gallons / min) through line 3A to valves 7 and 8, while a flow of approximately 77 l / min (17 gallons / min) reaches valve 6. In Fig. 1, the valves 6, 7 and 8 are shown in their zero position, in which the liquid is directed through the lines 14, 15 via the passage 16 to the tank will. In the zero position, the lines to the device are connected to each other and with the passage l6 via the line 3 connected so that the device 9, if necessary, can be operated by hand.

The amount of primary electricity is supplied through opening 4, which is installed in the valve 5 is determined. The pressure drop across this opening is used in order to bring a valve piston (slide, not shown) into position, which makes the flow independent of the work pressure in the right proportion. By varying the opening 4, the primary flow rate be increased or decreased accordingly »

The opening 22 is built into a valve 17 (Fig. 2), which is provided with a measuring spindle 21. With this, the size of the opening 22 in the Line I3 (Fig.l) can be varied. Normally the spindle 21 of the valve I7 is from the opening 22 pushed away by a spring 23, so that a ma-

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xiraal flow through the opening is possible,
and remains in this position until, for example, around 50at (700 psi) pressure from device 9i
that is a drill motor is required. If this pressure is exceeded, a corresponding increase in pressure appears in line 19 «this
Pressure increase acts on the end of the piston 20,
so that the spindle 21 axially against the pressure of the
Spring 23 is moved and the size of the opening 22 is reduced. This will increase the flow rate
to device 10 via valve 8 reduced to approximately 9 l / rain (2 gallons / min). When the piston 20
no longer feels the increase in pressure, the spring 23 moves the spindle 21 and opens the opening 22.
This increases the flow to valve 8 to approximately 13 l / min (3 gallons / min).

Thus, as long as there appears to be a rise in pressure on the piston 20, a flow of fluid of, for example, 9 l / min (2 gallons / min) is supplied to the device 10, which is a feed motor for the drill, so that it moves the drill at a speed of about 30 feet / min (12th feet / min) in
the material drives. If there is no increase in pressure on piston 20, the flow is increased to approximately 13 l / min (3 gallons / min), which increases the feed rate of the drill to approximately 6 m / min
elevated.

As long as the drill hits soft material, the pressure appearing on line 18 is relative small amount. However, when the drill reaches harder material, the pressure increases sharply until the

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Drill motor 9 stops. This situation is avoided by an anti-stop valve 2h in the feed line to the device 1CT. This valve 24, which is shown in Fig. 4, comprises a housing body 25 with an inlet 26 which is connected to the feed line 27 (Fig.l), and with an outlet 28 which is connected to the return line 29 (Fig.l) ) connected is. The inlet 26 communicates with a piston valve 3O1 which comprises a piston 3I _1, a spindle 32 and an opening needle 33. The valve is normally under tension so that the valve needle 33 rests against a seat 3 ^. This preload is supplied by a spring which is adjustably preloaded by a control device 35. The end of the piston 3I is arranged in a passage 36 which is connected to the feed line l8 (Fig.l) for the rotary movement.

If the motor 9 experiences a substantial resistance in rotation, a corresponding resistance occurs Pressure rise on line l8 (Fig.l), which also appears in passage 36. If this Pressure exceeds the resistance of the spring 3OA, the needle 33 is lifted from the seat 34, whereby the two passages 26 and 28 are connected. This makes the flow to the feed motor 10 reduced, and a standstill of the motor 9 is prevented. The greater the pressure appearing in passage 36, the further the valve 33 becomes from lifted off its seat and thereby reduced the drilling speed accordingly.

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Valves 6, 7 and 8 each have holding devices, which keep them in their chosen position. The valve 8 differs from the valves 6 and 7 insofar as it contains an automatic release ("kick-out") valve 37 (Fig.l). When the feed motor 10 has reached its maximum stroke, a pressure increase appears on the line 13A. When this pressure rise reaches a predetermined value, it releases the holding device 38 and lets the piston move under the spring pressure move to the reset position, reversing the direction of flow to motor 10.

When the motor 10 has reached a fully retracted position, appears on line 29 a pressure that builds up over 42at (600 p.s.i.). If you allow this pressure to build up, until the main relief valve opens, * the temperature of the liquid increases at a rate of approximately 125 kcal / min (500 BTU / min). This is extremely undesirable. Therefore it becomes a relief valve 39 provided in the flow circuit. This valve is set to open when the Pressure exceeds about 42 at (600 p.s.i.) and prevents a corresponding pressure in the High pressure circuit to valve 6 builds up.

If the valve is activated when the feed rate is reduced, if the drilling motor 9 stops, fails, relief valves 40 and 4l are in the Feed and return lines 42 and 43 (Fig.l) are provided. These relief valves 40, 4l are pilot

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actuates and draws the liquid to the tank, thereby preventing possible damage to the system will. Additional pilot operated relief valves 44 and 45 provide additional security against failure.

In use, the device 11, which is a hydraulic ram, blocks a drilling column between Top and bottom of a mountain tunnel, while the feed motor 10 drives the drill motor 11 along the column moves and drives the drill into the stratifications.

Preferably, the drilling column is hinged to the mining machine so that it can be folded over can when not in use. For positioning the column when needed for use is, a third valve 46 (Fig.5) is in the circle provided that the supply of liquid to a second hydraulic ram 47, which between attached to the column and mining machine controls.

Fig. 3 is a section through the valve 8 and shows in detail the construction of the holding or Trigger ("kick-out") device 37, piston (slide) 48 and relief valve 39.

The release device 37 comprises a tubular sleeve 49 which is attached to the piston (slide) 48 is attached and protrudes beyond the valve housing body. In the sleeve 49 is a second tubular

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screwed shaped part 51, at which one end ring 52 A is mounted, which acts as a pressure plate for a spring 5 2. This pushes the piston (Slide) 48 in the zero position (as shown).

A holding piston 53 is mounted inside the sleeve 49 and is pressed onto the piston 48 by a spring ^ . The retaining coil 53 pushes retaining balls 56 radially outwardly into the passages 57 in the wall of the sleeve 49 and into contact with one of the retaining grooves 58 formed in the housing 59 through the spring ^ k and its curved surface 55.

A valve spindle 60 runs coaxially through the holding piston 53, the head 6l of which is supported by the spring 63 is printed in contact with the seat 62. The spring 63 can be adjusted by the adjustment screw 64 will.

In use the line I3B communicates (Fig. 1) with the slot 68 in the housing body 50 of the valve (Fig; 3) and with the passages 69 and 7O, if the Valve piston 48 is in the zero position. The passage 70 leads together with the passage 67 to the line I5 (Fig.l) and allows the liquid to return to the tank via the line.

When the valve slide 48 in the direction of the arrow Y by means of a control handle which is attached to the free end 71

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of the piston 48 is moved, the slide parts 72 and 73 separate the passages 69 from Part 7O · This movement of the valve piston connects also the passage 68 with the passage 74 by means of a recess 76 on the valve piston 48. As a result the high pressure fluid flows through the slot 66 and the line 27 (Fig.l) and the motor 10 is driven thereby. The liquid, which returns from the motor 10, enters. at the opening 65 and passes through the passage 75 » the slide part 77 into the passage 67 and back to the tank.

When the feed motor 10 has reached its maximum position on the column and stops, it lifts the resulting pressure increase by means of a passage 78, the valve 60 from its seat 62 against the Holding piston 53 and moves it against the pressure of the spring 63 and releases the balls 56 from the holding grooves 58. This allows the spring 5I to push the piston 48 move into the zero position, whereby the liquid in passage I3B over the passage part 70 and the Line I5 can return to the tank.

When the piston 48 is moved in the opposite direction to the arrow Y, the passage pieces 69 and JO are again separated; the passage 75 is connected to the passage 68 and the passage 74 to the passage 67, whereby the direction of rotation of the feed motor 10 is reversed.

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The spring 5 2 could of course also be set up so that the piston 48 completely opposed the direction of the arrow ■ Y is moved, whereby the automatic drilling mechanism would retract. In this case, the high rise in pressure opens the occurs in passage 75 when the drill is fully withdrawn, the relief valve 39 and allows the liquid to return through passages 7 ^ and to the tank until the plunger is manually in the zero position is reset.

As shown in Fig. 3, the relief valve 39 is a poppet type valve which is progressive Relief of a pressure increase in passage 75 causes.

In some cases, more accurate pressure relief may be preferable. In this case the Relief valve part 79 replaced by a pilot relief valve with a relieved piston. Of the Piston (not shown) replaces valve rod 80, the rear face of the "piston" is replaced by a "Pressure passage relieved (balanced) from passage 87. The pilot can be built into valve 79 or be mounted separately and allows compensation fluid to passage 84 through, whereby a pressure increase in passage 75, the valve 79 against the pressure the spring 82 can move. This results in a bypass to the engine 10 and the high-pressure fluid cext returns to the tank.

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The control valve 8 has so far been described in an embodiment which is intended for use with the anti-stop valve of FIG. If necessary, however, the anti-stop valve 24 can be built into the valve 8, as shown in FIG. In this embodiment the body is provided with a first chamber 83 which is arranged between the passage 7k and the opening 66 and which is connected to the relief valve 39 through the passage 84. The chamber 83 is connected by an axial passage 85 to a second chamber 86 which is arranged between the passage 75 and the opening 65. The passageway 87 connects the chamber 86 with the relief valve 39. In the first chamber 83, a body 88 is mounted, which divides into two parts 89 and ^ O the chamber 83rd These are connected by passages 91 and 92. A piston valve 93 is arranged in the passage 91, the needle part 9 ¹ I of which can close the passage 9I, whereby the chamber parts 89 and 9O are separated. A spindle 951 protruding from the chamber 86 contacts the needle piece 9 ^ and forms the device with which the needle piece 94 is biased onto the seat 96 by the spring 97, whereby the passage 9I is normally closed.

With valve 48 held in the Y direction, high pressure fluid passes from passage Jk through chamber 89 to port 66 and conduit 27 and drives feed motor 10. When the drill hits hard layers, the pressure to rotate in line 18 increases. This increase in pressure also appears at the anti-stop valve inlet 99 via line 98 (Fig.l). This acts in valve 99

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Pressure rise on the piston 93

In the passage 91, a restrictor (throttle) 100 is arranged between the piston 33 and the inlet 99, which ensures a pressure drop in the passage 91. This prevents the valve yk from opening prematurely.

The pressure at which the anti-stop valve begins to open can be adjusted with the adjusting screw 101 set, which varies the compressive load on the spring 97.

When drilling in rock or the like, each attempt results in the penetration speed of the drill by increasing the feed pressure, either by stopping the drill motor, or in damage to the cutting edge

of the drill. Therefore it is desirable to have the correct one Maintain feed pressure so as to obtain the most effective penetration rate. if it is therefore assumed that the most effective penetration speed through an average layering is 3 «70 m / min (12 feet / min) at about 70 at (1000 p.s.i.), it is necessary to keep the fluid pressure proportional to be reduced if the drill encounters tougher layers.

In the present invention, this is accomplished in two ways. First, by the liquid flow to the control valve 8 with regard to the force

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wandes is controlled, which is necessary to rotate the drill in the layers. Second, by regulating the flow of fluid to the feed motor in terms of the amount of force required to rotate the drill into the stratifications. The first of these functions is performed by the valve of Fig. 2 which reduces the flow to valve 8 when the torque of the drilling motor increases and which increases the fluid flow when the torque decreases. The second function is carried out by the anti-stop valve by means of the piston 91 (FIG. 3), which responds to a pressure increase in the line l8. The piston 91 reacts to the increase in pressure and lifts the valve 9 ^ from its seat, whereby the liquid can return to the tank via the passages 85, 75 and 67.

The cone angle on the needle valve 9 ^ determines that Volume of liquid that is returned to the tank for a given pressure increase. It leaves thus recognize that the choice of the angle with respect to the rate of reduction of the feed rate of the pressure increase on line l8 (Fig.l) is determined.

The adjustment of the needle valve 21 (Fig.2) with respect to the opening 22 is carried out by a second piston-like part 21A which is screwed onto the valve 21 and forms the device, through which the spring pushes the valve into the open position. Part I7A of the body I7 removed and the valve 21 inside the piston-like part 21A with the screwdriver turned. The piston-like part 21A can there-

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because of the pin I7B, which is inserted into a slot 21B intervenes, does not turn.

Under certain circumstances, liquid can bypass piston 20 or valve 21 into area I7B lick and a hydraulic lock ("hydrauliclock") cause the valve not to work. This situation is avoided by having a drain hole 17c is provided which leads to the atmosphere or with a suitable return line, depending on the requirements, is connected in the flow circuit.

The fluid control valve device described above is particularly suitable for use with semi-automatic mining ceiling drills, however, it is not limited to this. It can be used on many other highly complex types of equipment be used.

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Claims (3)

666ü / ö6 / UO / gn - l6 - April 3 Ι97Ί EXPECTATIONS \ l. jSelf-compensating valve device for controlling a plurality of liquid-operated devices with regard to their primary liquid requirements, characterized in that it comprises a variety of selective spool (spool, "spool ¹¹ ") control valves, a primary flow divider that separates a supply liquid supplied to it into two volumetrically different flow paths, the first of which is directed to a first selective control valve that distributes the liquid flow to one of three liquid lines to a first liquid-operated device, while the second flow path to the other selective control valves and optionally distributed through one or more liquid lines to a large number of additional, individual, liquid-operated devices for their function control depending on the requirements, a pressure responsive device that provides a flow of liquid to one of the additional Devices gauges when the pressure of the liquid to the first device is above a predetermined value increases, - 17 - 409844/0305 6660/06 / UO / gn - 17 - 3 April 197'i a device with which the liquid flow to said, an additional device is reversed when this device reaches a maximum position. 2. Selector control valve for installation between a liquid-operated device and its associated Supply and return lines toJT Control of the volume of liquid that is fed to the device depending on the pressure, which is necessary for its operation, characterized in that it comprises a housing body with a liquid inlet passage and a liquid return passage, which are connected to a liquid supply or a liquid storage vessel can be, the selector control valve, the liquid-operated device that Liquid supply and the vessel at least part of a closed liquid circuit are; a piston (slide, "Spool ¹¹ )» which is in a chamber in the housing body
mer / is mounted and can move axially between first, second and third positions, in the first position connecting the inlet passage to a first passage connected to the device and connecting the outlet passage to a second passage, which is connected to the device, removing liquid from the inlet of the device in a 4098U / 0305 - 18 - 6660/06 / UO / gn - 18 - 3 April 197> i drives the first direction, the piston in the second position with the inlet passage connects to the return passage and in the third th position connects the inlet passage with the second passage and the outlet passage connects to the first passage, causing the device to be propelled in reverse will, the first passage including a portion defining a two-part chamber, the first of which Part has a valve that normally closes the first part from the other part and is connected to a piston 'which is arranged in a third passage, wherein the valve is biased towards the closed position and one passage is the third passage connects to a distant source of fluid, causing an excessive increase in pressure in this remote source of liquid causes the piston to move the valve against the biasing device and connecting the two chamber parts together, thereby removing some of the liquid from the first passage can get through the second chamber part and a fourth passage "to the back let-passage, whereby the operating speed of the liquid-powered Device is reduced. Selector control valve according to Claim 2, characterized in that the valve is a comprises a conical needle valve arranged and adapted to have an opening defining wall between the two parts of the chamber closes. 4098U / Q3Q5 - 19 - 6660/06 / UO / gn - 19 - 3 April Selector control valve according to claim 3 »thereby characterized in that the apex of the needle valve is connected to the piston, the needle valve into the other chamber part is movable and so progressively increases the flow of liquid between the two chamber parts. 5. Selector control valve according to claim 4, characterized in that it is a restrictor (Throttle) in the third pass. Anti-stop valve for installation in the supply and return lines to a liquid-operated Device for controlling the flow of fluid to this device as a function of pressure a liquid in one supply line to a second, remote, liquid-operated Apparatus characterized in that it comprises a body with a two-part chamber, an opening that defines a connection between the chamber parts, a needle valve that normally closes the opening, a first passage which connects a first of the chamber parts with a liquid inlet binds, - 20 - Α0984Λ / 0305 666O / O6 / UO / gn - 20 - 3 April 197 '* a second passage, which is the other part of the chamber connects to a liquid outlet, a cylinder with a piston arranged therein, which pushes the needle valve into the fully open Position can move, a spring device that normally pushes the needle valve closed, wherein the cylinder includes a liquid inlet which is connected to the supply line to the remote, connected to a liquid-operated device can cause an increase in pressure in the fluid supply to that remote device The plunger allows the needle valve to move to the fully open position, removing fluid from it the first chamber part flows into the other chamber part, wherein the needle valve is configured and arranged is that there is the flow of liquid through the opening depending on the value of the pressure rise in the fluid supply to the remote device increased to the operating speed of the first liquid-powered device to decrease. 7. Self-compensating valve device according to claim 1, characterized in that that includes the primary flow divider a housing body, - 21 - 409844/0305 6660/06 / UO / gn - 21 - 3 April 197 '* a high pressure liquid inlet, a passage extending through the housing body and the inlet with a first outlet connects, thereby defining a first of the fluid paths, a second passage extending through the housing body and the entrance with a connects the second outlet, which defines the other flow path, wherein the second passage includes a device by which the volume of the liquid, the passes through this, controlled with respect to a liquid back pressure in the first passage can be. β. Self-compensating valve device according to claim 7 »characterized by i c h η e t, that the device for controlling the volume of liquid passing through the second passage includes a restrictor housing mounted in the housing body and an opening which is arranged and arranged to have the second passage in two Parts divides, with a needle valve arranged inside the restrictor housing and on the Opening towards or away from dinser can be moved to control the volume of liquid that from a first part of the second passage near the inlet to a second part of the passage near the outlet, the re- 409844/0305 - 22 - 6660/06 / UO / gn - 22 - April 3, 197't strictor housing contains a cylinder in which a piston is arranged, which can move the needle valve at least towards the opening, the cylinder being connected by a third passage to the first passage, whereby a pressure increase of the liquid in the second passage opens the piston to the needle valve can move the opening to reduce its cross-section. 9 · Self-compensating valve device · according to Claim 8, characterized in that it contains a resilient device which pushes the needle valve away from the opening. 10. Self-compensating valve device according to Claim 9, characterized in that it has an adjusting device for Contains adjustment of the needle valve relative to the opening. 11. Self-compensating valve device according to claim 10, characterized in that that the adjustment device comprises a second piston-like part in the third Passage is arranged between the valve and the first piston, the valve being a Includes threaded spindle, which is of a complementary threaded opening in the second piston-like part is added. 409844/0305 - 23 - 6660/06 / U0 / gn - 23 - 3 April 12. Self-compensating valve device according to claim 11, characterized in that it is marked that the second piston-like part is arranged in a part of the cylinder, the one has a larger diameter than the part "'in which the first piston is arranged, wherein the second piston-like part slidably seated within the first cylinder part and the first piston slidably seated in the corresponding cylinder part and of sufficient length so that only a small part of it protrudes into the first cylinder part when the needle valve approaching the opening. 13 «Self-compensating valve device according to claim 12, characterized in that that it contains a device which the relative rotation between the second piston-like part and the housing prevented. Ik. Self-compensating valve device in combination with a ceiling drill, characterized in that the ceiling drill includes a column that can be placed between the ceiling and the floor of a tunnel, a liquid-operated cylinder device, which is attached to the column and can fix the column between the ceiling and the floor, - 24 - 409844/0305 6660/06 / ϋθ / ίζπ - 2'Jt - 3 April 197 '* a liquid-powered drill motor that is placed on the column and run there can, a liquid-powered drill feed motor, which can move the drill motor towards and away from the ceiling, the valve device comprising a variety of selective control valves of the piston (spool, "spool") type, a priority flow divider that divides a supply liquid supplied to it into two volumetrically separates different flow paths, the first of which is directed to a first selective control valve is that optionally, depending on the requirements, the liquid flow to one of two liquid lines distributed to the drill motor, or on a third liquid line to the tank, the other flow path being directed to the remaining selective control valves and optionally through one or more fluid lines to the cylinder assembly and the drill feed motor for whose function control is distributed depending on the requirements, wherein a pressure responsive device provides a flow of fluid to the drill feed motor gauges when the fluid pressure to the drill motor rises above a predetermined value, 409844/0 6660/06 / UO / gn - 25-3 April 197 ^; ± and wherein a device controls the direction of the liquid tss f-.roms to the drill feed motor reversed when this reaches a predetermined maximum position. 1.5 · Valve device according to claim 1Λ, characterized characterized in that a second one of the selective control valves comprises a housing body with a liquid inlet passage and a liquid return passage each associated with the second Communicate fluid path and a fluid storage vessel, a piston (slide, "spool") mounted in a chamber in the housing body and can move axially between a first, a second and a third position, wherein the piston in the first position connects the inlet passage with a first passage, which is connected to the Vorschtxbmotor, and connecting the release passage to a second passage connected to the advance motor is whereby liquid from the inlet drives the feed motor in a first direction, wherein the piston in the second position connects the inlet passage with the outlet passage , - 26 - 409844/0305 6660/06 / UO / gn. - April 26-3, 197'i and wherein in the third position the piston connects the inlet passage with the second passage and the return passage with the first Passage. Connects, whereby the feed motor is driven in the opposite direction, wherein the first passage contains ein.Teil that defines a two-part chamber, the first part before valve device, which normally has the first part from the other part closes and is connected to a piston "which is arranged in a third passage, wherein the valve device is biased towards the closed position and a passage is the third passage connects to the first passage, causing an excessive pressure increase in the first pass the piston move the valve device against the pretensioning device leaves, whereby the two chamber parts are connected to each other and part of the liquid from the first passage through the other chamber part and a fourth passage to the return passage can close, which reduces the working speed of the feed motor will. 16. Valve device according to claim I5, characterized gekennze i chnet that the valve device includes a comic-shaped needle that arranged and arranged to have an opening defining wall therebetween completes the two parts of the chamber. 409344/0305