EP0952354B1 - Fast-approach circuit for hydraulic motors and cylinders - Google Patents

Abstract

The switch is used with hydraulic oil motors (10) and cylinders (11). A fast-traverse unit (32) is fitted in the pressure branch (5) and the return branch (2), which interrupts the two branches under control. Another oil motor (18) is driven by the same hydraulic circuit, and possibly used to drive an oil pump (19), may be included in the fast-traverse unit.

Description

The invention relates to a rapid traverse for hydraulic oil motors and cylinders according to the generic term of Claim 1.

Such a rapid traverse circuit is known from US-A-5 251 705.

Furthermore, EP 0 797 027 A2 is a closed hydraulic system become known for driving a hydraulic motor, the Speed can be changed in that the Flow volume of the film motor can be changed accordingly. For this purpose, a swash plate pump is provided, which in their funding volume is changeable accordingly Swallowing volume and thus the speed of the to change the driven hydraulic motor.

The disadvantage of this known system is that it is a closed system, in which eventual Leakage oil losses cannot be compensated for easily can, because a suction from a tank is not possible.

The principle of this known circuit is a changeable one hydraulic transmission, which is accordingly of a Motor is driven, which one hand hydraulic motor and on the other hand a hydraulic pump drives.

Rapid traverse is not provided.

For machine tools and others in speed changeable drives, however, it is necessary that one used a rapid traverse in addition to a normal gear. Here is it is known to switch on a control pump, so a larger one Oil quantity to the rotating motor to be driven or the one to be driven Linear cylinder can be fed. However, this requires the addition of an additional pump in the drive system, what is associated with a high level of machine expenditure and what the manufacturing costs increased accordingly.

There is also a rapid gear shift for differential cylinders known where the area ratios are related to piston area to the piston ring surface (on the back of the piston) to reach different speeds.

The invention is based on the object To provide rapid traverse for such a drive, which is able to with no increased machine effort any existing circuits used to become.

To achieve the object, the invention is by characterized technical teaching of claim 1.

An essential feature of the invention is that in the existing hydraulic circuit consisting of the pressure branch and a rapid traverse block is switched on, which Rapid motion block the two branches (pressure branch and return branch) controlled interrupts that in this rapid traverse block from same hydraulic circuit driven oil motor available which in turn drives an oil pump, which the oil from the driven oil engine or the driven linear cylinder and directly onto the Pressure side of this driven element (rotary motor or Linear cylinder).

With the given technical teaching, the result is significant advantage that by switching on a separate rapid traverse block in the aforementioned, per se known hydraulic circuit it is now possible for the first time to operate a short circuit or bypass operation, so to speak, which consists in the fact that that of the driven Element (oil motor or linear cylinder) returning oil now no longer runs back into the tank, but that this oil now in the sense of a bypass circuit now the hydraulic driven pressure pump is supplied in the rapid traverse block and the normal pressure pump in the circuit runs continuously, so that this continuous, the already existing oil flow the additional Oil flow of the rapid traverse block is superimposed on the To achieve rapid traverse of the driven element.

With the given technical teaching, the result is Advantage that you can no longer use differential cylinders is dependent, but you can use conventional linear cylinders use the piston surface in both forward and in Reverse operation are the same. The same goes for of course for oil engines, which are now also available for the first time can be operated in rapid traverse in a simple manner because otherwise also with such oil engines Rapid traverse based on different Differential areas cannot be used. To this It is possible for the first time to use such oil motors with one Equip rapid traverse.

It is particularly advantageous that the invention Rapid traverse block as a separate block practically in the interruption of the normally existing hydraulic circuit used can be. This hydraulic circuit is in itself known manner from a spool, the Pressure connection uses a conventional pressure pump, which the pressure oil via an assigned pressure line to be driven consumer. The consumer Oil flowing through is returned via a return line fed to this spool and runs back into the tank.

In such a hydraulic line, consisting of pressure branch and the return load is now the rapid traverse block the figure turned that with the help of two Folding valves the previously mentioned hydraulic circuit is interrupted and instead that which flows in the pressure branch Oil to supply the associated with the rapid traverse block Hydraulic motor is used, which in turn one Hydraulic pump that drives the consumer returning oil sucks and directly back on the Feed side of the consumer feeds.

The invention therefore lies in the fact that to achieve a Rapidly an additional oil motor in the circuit which oil motor is switched on an additional oil pump drives that swallowed by the rotary motor (consumer) Volume no longer feeds directly to the tank, but instead feeds directly to the pump of the rapid traverse block. It is coming So no longer to a return flow into the tank, but to a direct short circuit on the pump of the rapid traverse block and this will make this pump available previously Volume significantly increased and the hydraulic motor as Consumers fed in the sense of a rapid traverse.

So it becomes practically the delivery rate for the hydraulic motor (Consumer) doubled or tripled because of one Additional pump of the rapid traverse block in the circuit is switched on.

Of course, the present invention is not based on limited the training of the consumer as a hydraulic motor; in the The meaning of the above description can of course a linear cylinder can also be used.

Likewise, the invention is not open to the arrangement of one Circuit with a pressure pump and a return in the Tank limited, but it can also be a closed one Circuit can be used.

Such a circuit can be used especially for hydraulic Winches, used for machine tools and the like, where it comes down to a rapid traverse using simple means overlay a normal circuit.

In particular, there is no need for an additional pump on the Pressure side of the control slide, as is the case in the prior art is known.

The rapid traverse block shown here is straightforward interchangeable, i.e. it only needs to be attached conventional hydraulic circuits of four in total Connection points and in these four connection points the Rapid traverse block can be used.

The rapid traverse block consists essentially of two, in Hydraulic circuit opposite control valves, between which the hydraulic motor and the pump are arranged are.

It goes without saying that there are other safeguards may be present, e.g. Seat valves and Pressure Switch, which the high pressure pump of the rapid traverse block from overload should protect.

The subject matter of the present invention provides not just from the subject of each Claims, but also from the combination of individual claims among themselves.

In the following, the invention is based on only one Execution path illustrating drawings explained in more detail. Here go from the drawings and their description further features and advantages of the invention Invention.

Figur 1:

Schematisiert eine Hydraulikschema einer Eilgangschaltung im Ruhezustand.

Figur 2:

Das Hydraulikschema nach Figur 1 in Eilgangstellung

Show it:

Figure 1:

Schematic of a hydraulic diagram of a rapid gear shift in the idle state.

Figure 2:

The hydraulic diagram of Figure 1 in rapid traverse

In Figure 1 it is shown that on a known per se Control spool 1, for example as a 4/3-way valve is formed, a pressure port 3 is arranged on which a pump 2 attaches. The pump delivers the pressure oil from one Reservoir not shown. In the position of Control spool 1 is no pressure promotion. It is further a return 33 is present, which opens into a tank 4.

A pressure branch 5 goes up from the control slide 1 the pump 2 in the appropriate switch position of the Control spool 1 delivered pressure oil in the direction of arrow 7 is promoted, the lines 15, 16 and 23, 24, the are assigned to the rapid traverse block 32, not yet acted upon are. The pressure oil therefore flows through the branch point 34 further up into line 27 and flows through there further branch point 35 and continues to flow into Arrow direction 7 on the pressure branch 5 in the oil motor 10, the is driven in rotation accordingly. Instead of Oil engine 10 shown can also use a cylinder 11 be the one with its piston rod Movement.

For the sake of simplification, the following will only be used the oil motor 10 is described as a consumer and it will not mentioned more that instead the transmitter shown 11 can be used as a consumer.

The oil flowing through the oil motor 10 arrives in the direction of the arrow 13 in the return branch 12, where it is over the branches 37, 38 flows down in the direction of arrow 13 and then over the line 23 flows to the tank 4.

With the above description, the state technology-related hydraulic circuit for the Pressurized oil supply to a consumer, e.g. an oil engine 10, described.

According to the invention is now in this hydraulic circuit Rapid traverse block 32 turned on, which essentially consists of the Lines 15, 16, 23, 24 also consists of the Switch valves 22 and 14 and the intermediate motor 18, which mechanically or hydraulically a pump 19 drives.

The two shown in the diagram Pressure relief valves 6 and 6a are only used for protection the pump motor unit 18, 19 so that it does not, for example pressure of 200 bar. For this In this case, these valves would switch through and one corresponding bypass from the pressure branch 5 to the return branch 12 provide.

There are therefore two pressure relief valves 6, 6a, because the consumer (oil motor 10) both in counterclockwise rotation can also be applied in clockwise rotation, so that then for the other application swapped the function of the branches becomes; then the return branch 12 and the return branch 12 then becomes the reverse branch 5.

This means that rapid traverse is also possible in the opposite direction possible, i.e. the consumer can run both left and right also controlled accordingly in rapid motion in rapid traverse become.

It is important that the rapid traverse over electrical Switch can be turned on. The counterclockwise rotation is e.g. the pressure switch 8 assigned during the clockwise rotation of the Pressure switch 8a is assigned. Accordingly, the actuated electrical pressure switch 8, then this controls the Switching valves 22 and 14 and the corresponding magnets Y2, Y3, Y5 on. The switching valve 9, 9a is thus controlled that the line 27 is interrupted and at the Branch 34 the oil in the direction of arrow 7 in the Line 24 flows in and flows through the switching valve 22. Here is now - according to this position of the Switch valve 22 - the line 20 for the engine 18 with Pressurized oil, which its oil via line 17th emits and via the also switched switching valve 14 in feeds the line 16 where the pressure oil in the direction of arrow 7 via line 5 to the consumer 10 with essential higher volume is supplied. This is because pump 19 is driven by the drive of the motor 18, which - according to the position of the Switch valve 22 - the return oil from the branch point 30 in the direction of arrow 29 through the lines 23 and 21 and feeds via line 39 to line 17.

It therefore follows that the pump 19 has a short circuit at branch point 30, because it is in the essentially prevents the oil in the direction of arrow 31 to Tank 4 flows back. This oil is now used to make the in the branch 5 to increase the amount of oil pumped, so that an increased amount of oil is supplied to the oil motor 10, the is switched to rapid traverse accordingly.

In the position shown, the consumer is in Left rotation in the direction of arrow 28 driven, the oil then no longer flows back via line 15; this line is shut off by the switching valve 14. The oil runs a lot more of the junction 37 in the direction of arrow 13 down over the open switching valve 9a and is at the Branch 30 in the sense of the above description divided up.

The largest part therefore flows via lines 23 and 21 pump 19 again, while only a smaller part flows to the tank 4 in the direction of the arrow 31.

It can even be provided that at the junction 30 in the opposite direction to the arrow direction 31 shown additional oil is sucked from the tank 4 to still additionally that supplied by the pump 19 to the consumer 10 Increase oil volume.

It has already been said at the beginning that those in the Lines 25, 25a switched on pressure relief valves 6, 6a only to protect the motor-pump combination 18, 19 against excess pressure.

In the above description, only the counterclockwise drive of the oil motor 10 in the direction of arrow 28 shown.

The clockwise rotation takes place in an analogous manner, whereby then corresponding switching valves 22, 14 are reversed, so to achieve counterclockwise rotation. Then they apply exactly same explanations as they were provided in analogous way.

With the given technical teaching, the result is Advantage, especially for winch drives with a simple Electrical circuit of the rapid traverse switched on and off can become what was previously not easily possible. To the prior art had namely the pump 2 one additional pump can be assigned to the delivery volume to increase this pump accordingly, which with essential higher machine costs and manufacturing costs was. There were also two instead of a simple pump regulated pumps 2 are used, also had to instead a simple oil motor 10, a regulated oil motor used what can now be avoided. This results in the main cost advantage of the invention Circuit consisting of the rapid traverse block 32. The as Separate component given rapid traverse block 32 can therefore also be retrofitted to existing circuits because of this Rapid traverse block only in the branches 34, 35, 37, 38 is switched on.

drawing Legend

1

Control spool (4/3-way valve)

2

pump

3

pressure connection

4

tank

5

Druckast

6

Pressure relief valve 6a

7

arrow

8th

Pressure switch 8a

9, 9a

switching valve

10

Oil motor (linear or rotary)

11

cylinder

12

return branch

13

arrow

14

switching valve

15

management

16

management

17

management

18

engine

19

pump

20

management

21

management

22

switching valve

23

management

24

management

25

25a line

27

management

28

arrow

29

arrow

30

branching point

31

arrow

32

Eilgangblock

33

returns

34

branching point

35

branching point

36

piston rod

37

branching point

38

Verzweigunsstelle

39

management

Claims (12)

1. Fast-approach circuit for hydraulic elements such as hydraulic motors (10) and cylinders (11), containing a hydraulic pump (2), a pressure branch (5) and a return branch (12) for conveying oil, wherein a fast-approach module (32) is connected between pressure branch (5) and return branch (12) and interrupts the two branches (5, 12) in a controlled manner, characterized in that the fast-approach module (32) contains a hydraulic motor (18) which, in turn, drives an oil pump (19) which draws oil from the driven element (10, 11) in the return branch (12) and delivers it directly back to the pressure side to the pressure branch (5) of this driven element (10, 11).
2. Fast-approach circuit for hydraulic motors (10) and cylinders (11) according to Claim 1, characterized in that the hydraulic pump (2) runs continuously, in particular while the fast-approach circuit (32) is operating.
3. Fast-approach circuit for hydraulic motors (10) and cylinders (11) according to Claim 1 or Claim 2, characterized in that the fast-approach module (32) is configured as a separate block.
4. Fast-approach circuit for hydraulic motors (10) and cylinders (11) according to any one of Claims 1-3, characterized in that the oil flowing in the pressure branch (5) is used to supply the hydraulic motor (18) assigned to the fast-approach module (32).
5. Fast-approach circuit for hydraulic. motors (10) and cylinders (11) according to any one of Claims 1-4, characterized in that the quantity delivered to the consumer (10, 11) in fast-approach mode is at least double.
6. Fast-approach circuit for hydraulic motors (10) and cylinders (11) according to any one of Claims 1-5, characterized in that a closed or open circuit is used.
7. Fast-approach circuit for hydraulic motors (10) and cylinders (11) according to any one of Claims 1-6, characterized in that the pressure branch and return branch are switched by a spool valve in a manner known in itself and in that no additional pump is provided on the pressure side (5) of the spool valve (1).
8. Fast-approach circuit for hydraulic motors (10) and cylinders (11) according to any one of Claims 1-7, characterized in that the fast-approach module (32) is connected to conventional hydraulic circuits at a total of four branching points (34, 35, 37, 38).
9. Fast-approach circuit for hydraulic motors (10) and cylinders (11) according to any one of Claims 1-8, characterized in that the fast-approach module (32) essentially consists of two opposing switching valves (14, 22) in the hydraulic circuit between which the hydraulic motor (18) and the pump (19) are arranged.
10. Fast-approach circuit for hydraulic motors (10) and cylinders (11) according to any one of Claims 1-9, characterized in that overload protection devices (6, 6a) are provided for the high-pressure pump (18) of the fast-approach module (32).
11. Fast-approach circuit for hydraulic motors (10) and cylinders (11) according to any one of Claims 1-10, characterized in that the hydraulic motor (18) drives the oil pump (19) mechanically or hydraulically.
12. Fast-approach circuit for hydraulic motors (10) and cylinders (11) according to any one of Claims 1-11, characterized in that the hydraulic pressure pump (2) acts on a spool valve (1) connected to the pressure branch (5) and to the return branch (12).

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