NO118116B - - Google Patents

Description

Device for hydraulic motor system.

The present invention relates to a

hydraulic motor system of the kind where a rotor body with approximately radially movable vanes is stored in a motor housing with two or more working chambers, and where a valve housing with a control valve for controlling working fluid to and from the various working chambers is arranged in connection with the motor housing .

As usual with such systems, the hydraulic motor system is thought to be connected to a

hydraulic pump of any design that delivers an almost constant pressure-fluid quantity per unit of time with varying pressure. The system can also be connected to a pump where the delivered pressurized fluid quantity per unit of time changes significantly when changing from one pressure range to another, but where the delivered pressure fluid quantity per time unit is approximately constant within each pressure range.

The connection between the motor system and the pump system also takes place in the usual way by leading a pressure line from the pump's pressure side to the valve housing for the control valve, while a return line is led from the same valve housing back to the pump's suction side.

It is also previously known to design the control valve so that the pressure line and return line are short-circuited through the valve housing when the valve is in the O position, i.e. when the hydraulic motor is stationary, while by moving this valve out of the 0 position one way or the other you can connect the inlet and outlet channels of the different working chambers to the pressure and return lines so that the engine can rotate in one direction or the other.

The system that the present invention relates to is particularly suitable for operation

of hydraulic winches etc. 1. where the hydraulic motor in one direction of rotation, i.e. when lifting a load, is exposed to a relatively large positive reaction force that tries to counteract the motor's rotation, while in the opposite direction of rotation it is exposed to a very small positive and even relatively large negative reaction force.

The system is not limited to just hydraulic winches and can be used for any operating device where the power consumption in one direction of rotation is greater than in the other, but for the sake of simplicity only hydraulic winches are discussed in the following.

It is in the nature of the matter that the flow direction of the working fluid through a working chamber must change when the engine's direction of rotation changes, and the inlet and outlet of a working chamber must therefore also change as the engine rotates one way or the other. As it is advantageous to have a fixed designation for inlet and outlet regardless of the direction of rotation, the term "inlet" is consistently used in what follows for the race that receives pressurized fluid when the engine is working against a large positive reaction force, i.e. during lifting of cargo, and correspondingly for the term "outlet".

In what follows, instead of pressure fluid or fluid, the term pressure oil or oil is used, although the system can of course be used for any other suitable liquid.

In a hydraulic motor with two or more working chambers, each working chamber forms its own circuit for the pressure oil and must therefore have its own inlet and outlet which must somehow be connected to the valve body. Usually this connection takes place by means of channels which are molded into the motor housing itself and which correspond to ports in the valve housing, which housing is flanged directly to the motor housing. For an engine housing that has two, three or even more working chambers, there are consequently many ducts that must be arranged in this housing, and in previously known designs the engine housing has become quite complicated due to the fact that two or more ducts must cross each other before they can be guided up to the valve housing.

The present invention aims to eliminate this drawback.

The invention is primarily characterized by the fact that the engine housing and valve housing with control valve are arranged in such a way that all inlet channels and outlet channels between working chambers and valve housing lie in the same plane throughout their entire extent without crossing each other. As a valve body and control valve, it is advantageous to use a cylindrical valve body with an internally displaceable slide of ordinary spool-shaped and tubular construction.

The invention is further characterized in that the outlet channelc for one or more working chambers is led through gates to one or more rooms arranged in the slide housing which are separated from the room in which the movable slide is located, which rooms communicate directly with the return line for the pressure oil, while the corresponding inlet channels through gates are led into the room in which the slide is located.

Another characteristic feature is that the said inlet channels are led into the slide housing through ports that are placed outside the slide's outer positions so that the slide does not cover or uncover these ports in any relevant position.

The system is further characterized by the fact that the slide in different positions, in addition to ports for the pressure and return line, only covers or uncovers ports for a single working chamber, and that these ports and the slide are so adjusted in relation to each other that this working chamber can be brought to to work in 2 or possibly 3 combinations, namely: 1. together with the other working chambers

2. neutral i.e. at idle

3. towards the other working chambers whereby it acts as a pump so that 2 or 3 speed steps are achieved by setting a single slide. Ports and slide are further adjusted in relation to each other in such a way that when the slide is moved out of the O position for

lifting loads, engages successive combinations that give ever-increasing speeds. In addition, the gates and slide are adjusted in relation to each other in such a way that when the slide is moved out of the O position for lowering the load, it only engages a single working chamber in reverse, while the other working chambers run at idle, whereby you only get one speed step with a speed that is equal to or close to maximum speed when lifting loads.

What is mentioned above regarding speed steps assumes that the pump delivers an approximately constant amount of oil per unit of time. If a pump is used where the amount of oil delivered changes, for example, when changing from one pressure step to another, you naturally get even more speed steps than mentioned above.

The system's operation will be explained in more detail below, as it is first shown used for a hydraulic motor with 3 mutually equal working chambers and then for a hydraulic motor with 2 mutually different working chambers, i.e. with different working volumes.

Fig. 1 shows a vertical section of the shaft for a hydraulic motor with 3 equal working chambers and with associated valve housing and control slide, and fig. 2 shows a section through the valve housing vertical to the section in fig. 1.

With reference to these figures, the engine's operating shaft is denoted by 1, on which is attached a rotor body 2 with radially displaceable vanes 3 which are stored in slots 4.

The rotor body 2 is stored in the engine housing 5 which contains the working chambers 6, 7 and 8. The direction of rotation when lifting a load is indicated by the arrow shown.

Work chamber 6 has inlet channel 9 and outlet channel 10. Work chamber 7 has inlet channel 11 and outlet channel 12, and work chamber 8 has inlet channel 13 and outlet channel 14.

As mentioned earlier, all channels lie in the same plane, and no channels cross each other.

Flanged to the motor housing 5 is a valve housing 15 which has ports that correspond to the aforementioned inlet and outlet channels. Channels 9, 10, 11, 12, 13 and 14 thus correspond respectively to ports 16, 17, 18, 19, 20 and 21 in the valve housing.

In the slide housing 15, an axially displaceable slide part body 22 is inserted. This is a normal and simple tubular and reel-shaped slide with two fixed flanges 23 and 24. The tubular part is led a little way past the flange 24, and at the end of this part is placed a loose flange 25 which can move a certain distance in the axial direction independently of the slide. This movement is limited by the bolts 26 which are attached to the slide itself.

The slide body 22 can be moved axially with the help of the rod 27 which is attached to the slide body at the lower end by means of joints and at the upper end by means of joints is attached to the arm 28. This arm is again wedged on a shaft 29 which is stored in the lid 30 The shaft is led out through the stuffing box and can be turned by hand using a handle not shown.

The outlet from the working chamber 7 is led through the channel 12 and the port 19 into an annular space 31 which is separated from the space in which the sliding body 22 is located. The space 31 is formed by the ring-shaped part 32 which is mounted in the slide housing by means of screws or the like.

The outlet from the working chamber 8 is led through the channel 14 and the port 21 into an annular space 33 which is likewise separated from the slide space. The space 33 is formed by the annular part 34 which is mounted in the slide housing or can also be molded in one with this.

The rooms 31 and 33 are, by means of the ports 35 and 36 respectively, in connection with the return channel 37, which in turn is connected to the return line leading to the pump. The return line is denoted by 38. From the pump, a pressure oil line 39 leads to the pressure channel 40 which, by means of the port 41, is connected to the interior of the slide housing. From the inside of the slide housing, a port 42 leads out to the return channel 37 and thus to the return line 38.

For a more detailed explanation of how the flow of pressurized oil proceeds through the different channels at different positions of the slide, refer to fig. 3, where the hydraulic motor is drawn schematically, and where the various figures a—e schematically show the slide in the various appropriate positions. It is in fig. 3 used exactly the same designations for ports and channels as used in figures 1 and 2.

O position.

This position is shown in fig. 3b. The slide is then in such a way that it short-circuits the ports 41 and 42 between the flanges 23 and 24, and pressurized oil entering through the port 41 exits through the port 42 without coming into contact with the working chambers. If there is now a load hanging in the winch, the motor will try to rotate in the opposite direction of the arrow and thus try to push oil into the slide housing through ports 16, 18 and 20. However, this part of the slide housing is completely shut off, so the motor must stand still and the load keep calm.

I position.

This position is shown in fig. 3c, and the slide has here been pushed down a step so that the flange 24 has come under the port 41. Pressurized oil now flows in through the port 41 and past the loose flange 25, which has now • lifted somewhat, and into the interior of the slide housing. From here, pressurized oil flows on through ports 16, 18 and 20 to the working chambers 6, 7 and 8. All working chambers are thus supplied with pressurized oil, and the motor will rotate in the direction of the arrow and the load will be lifted.

Return oil from working chamber 6 runs into the slide housing through port 17 and further out through port 42. Return oil from working chamber 7 runs into the slide housing through port 19 and further out through port 35. Return oil from working chamber 8 runs into the slide housing through port 21 and out through the gate 36. As previously mentioned, the gates 35, 36 and 42 lead out into the return channel 37 and to the return line 38. All three working chambers now work together, and the hydraulic motor can lift the maximum load and rotates at a normal speed.

Disposition.

This position is shown in fig. 3d, and the slide has here been pushed down another step so that the flange 23 has come under the port 16. Pressure oil to and return oil from the working chambers 7 and 8 runs in exactly the same way as in the I position of the slide, but the slide now short-circuits the ports 16 and 17 so that the working chamber 6 runs at idle without the supply of pressurized oil. The oil flows into this chamber through port 16 and out through port 17. There are now only two working chambers working together, and the engine can lift 2/3 of the maximum load while the speed becomes 1.5 times normal speed.

Ill position.

This position is shown in fig. 3e, and the slide has here been pushed down another step so that the flange 24 has come under the port 17. Pressure oil to and return oil from the working chambers 7 and 8 still run in the same way as in position I and position II of the slide, but working chamber 6 now draws oil from the return line through ports 42 and 16 and pushes oil out through port 17 and into the slide housing's pressure chamber. Working chamber 6 consequently acts as a pump and thereby neutralizes ct of the other two working chambers so that only one working chamber becomes effective. There is now only one working chamber working, and the engine can lift 1/3 of the maximum load while the speed becomes 3 times normal speed.

R position.

This position is shown in fig. 3a, and the slide is here pushed from the O position and a step upwards so that the flange 23 has come over the port 42. The pressure oil now passes through the port 41 and further through the port 17 to the working chamber 6, and the motor will rotate in the opposite direction, i.e. towards the arrow. Return oil from working chamber 6 runs out through ports 16 and 42 to the return line. The other working chambers work at idle as working chamber 7 draws oil from the return line through ports 35 and 19 and pushes oil through ports 18 and 42 back to the return line, and working chamber 8 similarly draws oil from the return line through ports 36 and 21 and pushes oil back to return line through ports 20 and 42. The speed in this position is the same as in position III, i.e. 3 times the normal speed.-

R position is only relevant when lowering an empty hook. When lowering the load, the slide is moved only slightly upwards from the O position whereby the oil which will be pushed out by the load through ports 16, 18 and 20, is throttled through port 42 which is then only slightly uncovered. By regulating this throttling, the speed at which the load is lowered can be regulated within wide limits. You can also regulate the speed within each speed step by setting the slide in intermediate positions whereby throttling or throttling occurs.

With the device described here, by maneuvering a single handle, three speed steps are obtained when lifting a load, and the speed steps are engaged in the most favorable order, namely: first low speed, then medium speed and finally maximum speed. When reversing the motor's direction of rotation, i.e. when lowering the empty hook, maximum speed is engaged immediately, which is also advantageous.

The invention can also be used for a hydraulic motor with only two working chambers, and this is shown in more detail in figures 4, 5 and 6. In these figures, exactly the same designations are used for the various parts as in figures i, 2 and 3. Then as there are now only two working chambers that must have channels for inlet and outlet, the system naturally becomes simpler.

Fig. 4 shows a vertical section of the shaft

for a hydraulic motor with two different working chambers, i.e. with different working volumes, and with associated valve housing and control slide: Fig. 5 shows a section through the slide housing, the vertical section in fig. 4.

With reference to these figures, the engine's drive shaft is denoted by 1, on which is attached a rotor body 2 with radially displaceable vanes 3 which are stored in slots 4.

The rotor body 2 is stored in the engine housing 5 which contains the working chambers 6 and 7, of which working chamber 7 has the largest working volume.

Work chamber 6 has inlet channel 9 and outlet channel 10, and work chamber 7 has inlet channel 11 and outlet channel 12.

Contrary to what is shown in fig. 1, the outlet channel 12 is led into the opposite end of the slide housing. This is done to get a symmetrical engine housing. It appears from fig. 4 that here, too, all channels lie in the same plane, and no channels cross each other.

Flanged to the engine housing 5 is a valve housing 15 which has ports that correspond to

the aforementioned inlet and outlet channels. Channels 9, 10, 11 and 12 thus correspond respectively to ports 16, 17, 18 and 19.

In the slide housing 15, a pre-displaceable slide body is inserted which has exactly the same design and the same designations as shown in Figures 1 and 2 and is adjusted by exactly the same type of adjustment mechanism. Reference is therefore made to the previous description of these parts above.

The outlet from the working chamber 7 is led through the channel 12 and the port 19 into a room 31 formed in the slide housing, which is separated from the room in which the slide body is located.

The room 31 is connected by means of the port 35 to the return channel 37 which is connected to the return line 38, which line leads to the pump.

From the pump, a pressure oil line 39 leads to the pressure channel 40 which by means of

port 41 is connected to the interior of the slide housing. From the inside of the slide housing, a port 42 leads to the return line 38 through the return channel 37.

Too close. explanation of how the flow of pressure oil proceeds through the different channels at different positions of the slide, refer to fig. 6, where the hydraulic motor is drawn schematically, and where the figures a—e show the slide in different relevant positions. It is in fig. 6 used exactly the same designations for ports and channels as used in figures 4 and 5.

O position.

This position is shown in fig. 6b and is analogous to fig. 3b. The slide short-circuits ports 41 and 42, and pressurized oil enters through port 41 and exits through port 42 without coming into contact with the working chambers.

With a load hanging in the winch, the motor will try to rotate in the opposite direction of the arrow and thus try to push oil into the slide housing through ports 16 and 18, but this part of the slide housing is completely shut off, so the motor must stand still and the load hang still.

/-score.

This position is shown in fig. 6c and is analogous to fig. 3c. Pressurized oil now flows through port 41 into the slide housing and on through ports 16 and 18 to the working chambers 6 and 7. Both working chambers are thus supplied with pressurized oil and the motor will rotate in the direction of the arrow and the load will be lifted. Return oil from working chamber 6 runs into the slide housing through port 17 and out through port 42. Return oil from working chamber 7 runs into the slide housing through port 19 and out through port 35.

As previously mentioned, the ports 42 and 35 lead to the return channel 37 and further to the return line 38. Both working chambers now work together, and the hydraulic motor can lift the maximum load and rotates at normal speed.

II position.

This position is shown in fig. 6d which is analogous to fig. 3d. Pressure oil to and return oil from working chamber 7 runs in the same way as shown in fig. 6c for position I, but the slide now short-circuits ports 16 and 17 so that working chamber 6 runs at idle without the supply of pressure oil e. The oil flow for this chamber runs in through port 16 and out through port 17.

If the working cross-section for the largest chamber is denoted by F and for the smallest chamber by f, the motor in this position will lift F/(F -|- f) times the maximum load while the speed becomes (F -I- f)/F times normal speed .

III position.

This position is shown in fig. 6e which is analogous to fig. 3rd. Pressure oil to and return

oil from working chamber 7 flows exactly in the same way as shown in position I and position II, but working chamber 6 now draws oil from the return line through ports 42 and 16 and pushes oil through port 17 into the pressure chamber of the slide housing. Working chamber 6 consequently acts as a pump and thus neutralizes part of working chamber 7 so that the effective working volume is equal to the difference between working volumes for working chambers 7 and 6. The engine can now lift (F—f)/(F + f) times the maximum load while the speed becomes (F -|- f)/(F—f) times normal speed.

R position.

This position is shown in fig. 6a and is analogous to fig. 3a. Pressurized oil now passes through port 41 and further through port 17 to working chamber 6, and the motor will rotate in the opposite direction, i.e. against the arrow. Return oil from working chamber 6 runs out through ports 16 and 42.

Working chamber 7 works at idle and draws oil from the return line through ports 35 and 19 and pushes oil back to the return line through ports 18 and 42. The speed in this position is (F + f)/f times normal speed.

Lowering the load and regulation of speed within each speed step takes place as explained above.

By operating a single handle, you also get three speed steps for lifting loads, and the different speed steps are engaged in the same favorable order as shown for a 3-chamber engine. When reversing the motor's direction of rotation, i.e. for lowering the empty hook, a speed is immediately engaged which will be close to the maximum speed when lifting a load. It is immediately seen that if one makes F=2f, maiTi gets exactly the same ratio between the speed steps as shown for a 3-chamber engine with equal working chambers.

If it is desired to have only two speed steps for lifting loads, the III positions can of course be omitted, and a 2-chamber engine can then be made with equal working chambers.

The invention is not limited to only hydraulic motor units, but can also be used for hydraulic pump units where the delivered liquid quantity per unit of time is desired to be regulated in certain steps, without going outside the scope of the invention.

Claims (8)

1. Device for a hydraulic motor-ener pump system of the kind where a rotor body with approximately radially moving vanes is stored in a housing, which has two or more separate working chambers with inlet and outlet channels, the openings to the outside are on the same side of the housing, and where this housing is flanged to a valve housing with an associated control valve for controlling working fluid to and from the various working chambers, which valve housing has ports that are in connection with the inlet and outlet channels for the working chambers, characterized in that the inlet channels (9, 11, 13 ) and the outlet channels (10, 12, 14) between working chambers (6, 7, 8) and valve housing (15) lie in the same plane so that no channels cross each other. 2. Device as stated in claim 1 where the working fluid is controlled by an axially displaceable slide in a cylindrical housing, characterized in that the outlet channels (12, 14) for one or more working chambers through ports (19, 21) are led to one or several rooms (31, 33) arranged in the slide housing which communicate directly with the return line (37) for the working fluid and are otherwise pressure-tight and separated from the room where the displaceable slide moves. 3. Device as stated in claims 1-2 where the inlet channels for the working chambers are led through gates into the room where the displaceable slide moves, characterized in that the inlet ports (18, 20) for one or more working chambers are placed outside the outer positions of the slide so that the slide (22) does not in any current position cover or uncover these ports. 4. Device as stated in the claims 1-3, characterized in that the slide (22) in the various relevant styles — apart from the ports for pressure and return line (41, 42) — only covers or uncovers the inlet ports (16) and the outlet ports (17) for a single working chamber ( 6). 5. Device as stated in claim 4, characterized in that the one working chamber (6) — when the slide (22) is moved out from the 0 position for lifting a load — can be made to work in the following three combinations, namely: 1: together with the other working chambers, 2: neutral, i.e. idling, 3: opposite the other working chambers where in that it acts as a pump, so that three different speed steps are achieved. 6. Device as stated in claims 4-5, characterized in that the slide (22) — when it is moved out of the O position for lifting a load — engages successive combinations which give increasingly higher speeds. 7. Device as stated in claims 4-6, characterized in that one working chamber (6) — when the slide (22) is moved from the O position for lowering the load — is brought to work in reverse while the other working chambers (7, 8) runs at idle whereby maximum or near maximum speed is achieved. 8. Device as stated in claims 1-7 where the motor or pump housing has two working chambers with different working volumes, characterized in that the working chamber with the smallest working volume is made to work in the combinations stated in claims 5-7.