FI123755B - Pressure medium system and pressure medium component as well as hydraulic splitter - Google Patents

Abstract

The invention relates to a pressurized-medium system, which includes a pressurized-medium source (15) and a double-acting actuating cylinder (14). The pressurized-medium system also includes a directional control valve (18) and pressurized-medium conductors (19). In addition, the pressurized-medium system includes a booster cylinder (21), which is fitted between the directional control valve (18) and the actuating cylinder (14), as well as a control element (37) fitted between the directional control valve (18) and the booster cylinder (21), for leading the pressurized-medium to the booster cylinder (21) and from there to the actuating cylinder (14). The pressurized-medium system further includes a rapid-travel valve (20), which is arranged between the directional control valve (18) and the actuating cylinder (14) in order to recirculate the pressurized medium from the return line (17) to the feed line (16) of the operating cylinder, in order to increase the work velocity of the actuating cylinder (14), in such a way that, together with the control element (37) and the booster cylinder (21), three velocity and power ranges (P1, P2, P3) are formed in the pressurized-medium system. The invention also relates to a pressurized-medium component and a hydraulic splitter.

Description

PRESSURE MEDIA SYSTEM AND PRESSURE COMPONENT COMPONENT AND HYD RODS

The invention relates to a pressure medium system comprising 5 - a pressure medium source, - a double-acting actuating cylinder with a supply line and paluulinj a, - a directional control valve for controlling the actuating cylinder, paineväliainejohteet connected via the pressure medium source 10 to the directional valve actuating cylinder and back, and arranged between the directional valve and the actuating cylinder speed valve of the pressure medium circulating drive cylinder from the return line to the feed line drive cylinder to increase work speed.

The invention also relates to a pressure medium component as well as to hydraulic cylinders.

The pressure medium system of the introduction is used, for example, in a hydraulic log splitter, also called a valve machine. The hydraulic logger has a buffer used with a double-acting hydraulic cylinder. The wood to be cut by the ram is pushed against the splitting blade. For example, straight and knot-free wood splits with even a small amount of force, so to speed up splitting, the pressure medium system includes a quick-action valve to circulate 25 pressure media to increase the working speed of the drive cylinder. In this case, the force of the drive cylinder is about half the maximum force. The maximum force is measured mainly on the basis of the hydraulic diameter and the size of the wood to be split and the required splitting length. In practice, the larger the hydraulic cylinder 30, the slower the splitting speed. Correspondingly, a small hydraulic cylinder achieves rapid work movement, but the splitting force remains modest. The same problem occurs in other applications that require a long work stroke and high power.

It is an object of the present invention to provide a novel pressure medium system that achieves a combination of rapid movement and high force in a small and compact size. It is a further object of the invention to provide a novel pressure medium component by which the power of the system can be simply increased. It is a further object of the invention to provide a new type of hydraulic diameter which is more versatile and efficient, but easier to use. Characteristic features of the pressure medium system of the present invention are set forth in the appended claim 1. Similarly, features of the pressure medium component of the invention are set forth in the accompanying claim 9. Further features of the hydraulic combined with 15 additional propulsion components. Advantageously, the control is automatic as the system speed and power changes according to the particular situation. This makes the system easy to use and, above all, fast and efficient. Such has previously been impossible to achieve or at least required complex and costly structures. The pressure medium component of the invention is a compact unit that can be placed in various systems to increase propulsion. The hydraulic logger achieves a combination of rapid movement and high power, which speeds up work with sufficient power to split even large logs 25.

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The invention will now be described in detail with reference to? to the accompanying drawings illustrating an embodiment of the invention, where 00 00 with 1 30 m

LO

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LO shows the hydraulic split, O) o Fig. 2 shows a schematic diagram of the system according to the invention, Fig. 3 shows the actuators of the system according to the invention partially in section.

3

Figure 1 illustrates a system according to the invention in a hydraulic die assembly. Only a portion of the body 10 provided with a buffer 11 and a splitting blade 12 is shown here. The location and height of the splitting blade can be adjusted to divide the wood into more than two sections. In Fig. 1, a block 11 is provided in the rear position of the buffer 11, whereby a wooden block 13 can be placed between the buffer 11 and the splitting blade 12, except for the bumper. The actuating cylinder 14 moving the buffer 11 is disposed within the buffer 11 and the piston rod of the actuating cylinder 14 is secured to the front end of the buffer 11. The other end of the drive cylinder is secured to the frame 10. In this case, the movement of the drive cylinder results in a log pushed against the hal-15 cutting blade by a bumper. When the log is ruptured, the tank returns to the rear position.

Figure 2 illustrates in greater detail the structure of the system, and in particular the wiring diagram. Firstly, the system includes a pressure source 20 material source 15, which in the hydraulic logger is provided with a hydraulic pump driven by an electric motor or a hydraulic outlet of a work machine such as a tractor (not shown). In Figure 2, the pressure medium source 15 is depicted by an arrow next to an icon representing a pressure medium tank. The system further comprises a double-acting actuator cylinder 14 provided with a feed line 16 and a return leg 17, and a directional valve 18 for controlling the actuator cylinder 14. Here the directional valve is of the normally closed type. In this case, it is necessary to change the directional valve (eg manually) to control the drive cylinder.

30

To circulate pressure medium, the system includes pressure medium conductors 19 connected from pressure medium source 15 through a directional valve 18 to drive cylinder 14 and back. The pressure medium source can then pressurize the drive cylinder 35 and guide it forward and backward. In the illustrated embodiment, a rapid movement valve 20 is further provided between the directional valve 18 and the drive cylinder 14. The rapid movement valve is used to circulate pressure medium from the return cylinder 17 of the drive cylinder to the feed line 16 to increase the operating speed of the drive cylinder 14. In practice, the speed valve is used to combine 5-lift cylinders of the piston and the piston rod-side to each other of forward operating pressure range of motion without affecting the use of the return movement of the cylinder. Thus, the forward movement of the drive cylinder is accelerated relative to the piston and piston rod areas. That is, in the uncontrolled central position of the high-speed valve 10, the return line of the drive cylinder and the feed line are interconnected. In the embodiment shown, the use of a quick-motion valve speeds the movement within the operating pressure range by a factor of two. Preferably, the high-speed valve is a valve which opens automatically at a certain pressure, such as in Figure 2, or a mechanical valve (not shown) operated manually. The high-speed valve can also be used with control logic.

According to the invention, the system further comprises a pressure boost cylinder 21 disposed between the high-speed valve 20 and the feed line 16 of the drive cylinder 14. The booster cylinder can increase the maximum pressure of the pressure medium source, thereby providing an even higher pressure on the drive cylinder. At the same time, the available power increases. The system further includes a pressure-controlled sequence valve 22 disposed between the high-speed valve 20 and the booster cylinder 21 25, which is coupled to the booster cylinder 21 so that when the pressure rises, the pressure in and further to the drive cylinder 14 to increase the drive force. A sequence valve is also called a priority or tracking valve. The back pressure compensated sequence valve releases the pressure medium behind the piston of the pressure boost cylinder when the force of the drive cylinder threatens 35. The system can also be controlled manually or by, for example, control logic using, for example, electric or pneumatic actuators.

The system described above provides many advantages.

5 The system is particularly advantageous in applications where mainly rapid labor movement is required, but only high momentum is required. The combination of the drive cylinder and the booster cylinder can replace a large and slow drive cylinder or two parallel drive cylinders with a twice as fast, yet equally powerful system. In addition, the system is compact and the controls are versatile, easily automated and adjustable. The operation of the system will be described in more detail later.

Figure 3 shows a pressure medium component of the invention adapted to be connected to a pressure medium system. Here, both the drive cylinder 14 and the booster cylinder 21 are shown at the beginning of their work movements. According to the invention, the directions of movement 20 of the drive cylinder 14 and the booster cylinder 21 are arranged opposite. In this case, the forces caused by the movements of the pistons are sometimes partially canceled, which reduces the vibration and otherwise reduces the load on the system. Figure 3 illustrates the direction of movement of the cylinders with arrows. Further, the drive cylinder 14 and the booster cylinder 21 are arranged in substantially one to 25 directions and secured to one another. In this case, the drive cylinder can be used to support the booster cylinder. Thus, for example, a conventional drive cylinder can easily be replaced by a pressure medium component according to the invention.

The pressure medium component further comprises a high-speed valve 20, which according to the invention is arranged in the same valve block 23 as the pressure-controlled sequence valve 22. The valve block 23 is shown in particular in Figure 3, where the connections of the valve block are indexed as in Figure 2. Here, the pressure medium conductors are from the pressure medium source 35, the pressure line 24 connected to the connection D1. Similarly, tank line 25 is connected to interface D2.

6 The supply line of the drive cylinder 14 is connected to the connection U2 and the return line 17 to the connection U1. The fifth connection is B2, which is connected to the supply line 16 'of the booster cylinder 21. In addition, the booster cylinder 21 of the high-pressure side are combined been five-T-connector into the drive cylinder 14 to the feed line and the low pressure side of the return line 26 coupling the actuating cylinder 14 to the return line 17. Thus, high pressure resistant tubing to a minimum. In this embodiment, the piping in question is only from the connection U2 of the valve block 23 to the actuator cylinder 14. The other pressure medium guides can be dimensioned according to the non-elevated maximum pressure of the pressure medium source.

In Figure 3, the valve block 23 is shown slightly separate from the drive cylinder and the booster cylinder. According to the invention, the valve block 15 may be supported on a booster cylinder to form an increasingly compact structure. In addition, the valve block can even be integrated as part of the booster cylinder to form a single integral pressure medium component. A new component can easily upgrade existing systems. However, when forming a new system, a heavy-walled drive cylinder is used. In other words, the wall of the drive cylinder is thicker than normal, which makes it possible to utilize a pressure significantly higher than the normal operating pressure provided by the booster cylinder. Exemplary calculations 25 will be presented later.

Figure 3 also shows a novel design of the booster cylinder. According to the invention, the pressure boosting cylinder 21 consists of a low pressure part 28 and a high pressure part 29 which are connected end-to-end 30 by a spacer 30 to extend one another. Such a structure is simple to fabricate because the walls of the low pressure section and the high pressure section can be made of different wall-strength pipe sections, which are then connected to one another by means of a spacer. Naturally, the wall of the high pressure section is stronger 35 than the wall of the low pressure section. In addition to the double structure, the pressure boost cylinder also differs with respect to the pressure build-up 7. According to the invention, the increased pressure is exerted solely by the piston rod projecting into the high pressure part, without a separate piston. This simplifies the structure, facilitates compaction and increases durability. In practice, normal seals are sufficient to seal 5 piston rods. More specifically, the low pressure member 28 includes a piston 31 provided with a piston rod 32 sealed in the spacer 30 and adapted to be a functional piston of the high pressure member 29. The increase in pressure is mainly influenced by the ratio of the piston rod to the piston areas 10. The piston 33 and piston rod 34 of the drive cylinder 14 are partially shown in Figure 3.

One preferred embodiment is the hydraulic ram sections shown in Fig. 1, which includes a body 10 with a splitting blade and a bumper 15 for actuating a hydraulic medium system according to the invention. The drive cylinder 14 and the pressure boosting cylinder 21 belonging to the pressure medium system are preferably attached to one another and arranged inside the buffer 11. The compact package is then protected inside the buffer. In addition, the hydraulic fractures can be upgraded by replacing the original drive cylinder with a new, stronger wall driven cylinder and the pressure lubricant component of the invention. The end result is three automatically operating speeds and power ranges, which makes the hydraulic-25 splitter on the one hand quick, but at the same time efficient without complicated and large structures.

In the hydraulic splitter shown, the drive cylinder is a conventional double-acting hydraulic cylinder, but is provided with 30 ordinary thick-walled cylinder tubes. A pressure boosting pressure component is mounted on the drive cylinder here. The booster cylinder may also be adjacent to the drive cylinder. In the system of the invention, unlike in prior art applications, the pressure is increased by pushing the piston rod of the low pressure part only into the oil space of the high pressure part. From the high pressure part, the pressurized oil is supplied to 8 reinforced drive cylinders, thereby providing a higher driving force than before without changing the capacity of the pressure medium source.

5 The magnitude of the elevated pressure is determined by the ratio of the piston rod to the piston surface area of the low pressure part. The increased pressure is mainly used only for the temporary need for additional power. In the embodiment shown, the increased pressure during each stroke of the drive cylinder is available for a distance of about 100 mm.

10

The hydraulic splitter is guided back and forth by a directional valve like a normal double acting hydraulic cylinder (Figure 2). The flow is controlled by a directional valve to a valve block according to the invention which automatically controls the system 15 between three speeds of movement and a force depending on the need for force. The valve block according to the invention forms a valve unit which combines three separate valves into one compact unit. The unit is compact and the number of external pipes and hoses is kept to a minimum. Despite the increased pressure, expensive high pressure hoses may not be needed at all thanks to the valve unit. Thus, the structure of the system according to the invention is compact and simple.

The drive cylinder operates in the same way as a normal double-acting hydraulic cylinder. The following example illustrates a system with a maximum pressure of 180 bar for a pressure medium source. When the resistance is low, the drive cylinder operates in a so-called rapid movement, whereby the oil on the piston rod side is circulated through the rapid movement valve in the valve block behind the piston. The quick stroke is 30 fast, but only the force corresponding to the actuator piston rod area is used. In this example, the swing range is 0 to 130 bar.

When the oil pressure in the system rises above 130 bar, the quick stroke 35 automatically shuts off. In other words, the pressure-controlled quick-change valve changes its position, whereby the oil begins to circulate from the piston rod side 9 to the tank and the pressurized oil goes just behind the piston. At the same time, the movement speed of the drive cylinder is halved, but the force is doubled. This operating range is in the example 130-160 bar. As the resistance continues to increase, the pressure 5 will still rise in the system. In the example at 160 bar, the force of the drive cylinder threatens to run out as the maximum system pressure is approached. In this situation, the booster cylinder is activated. However, the drive cylinder continues to advance because of the maximum system pressure of 20 bar still available. The sequence valve in the valve unit opens at 160 bar at its setpoint and releases oil behind the booster piston and begins to push the piston rod into the high pressure oil chamber at 160 bar. At the same time, the pressure begins to increase in addition to the oil space in the high pressure section in the supply line of the drive cylinder and thus on the piston side of the drive cylinder. Due to the increase in pressure, the pressure-controlled check valve 35 in the valve block closes immediately due to the differential pressure and raises the pressure in the drive cylinder up to 440 bar, while the pressure in the cylinder of the booster cylinder is 180 bar. 20 Pressure-controlled non-return valve prevents elevated pressure escaping through system pressure relief valve to tank. At the same time, the speed of movement of the drive cylinder is about halved, but the force increases about twice. The pressure control sequence valve of the above criterion is set to be 5-20%, more preferably 25-10-15% lower than the maximum pressure of the pressure medium source.

In this case, the movement of the drive cylinder will continue without stopping while the system control operates automatically.

If the resistor succumbs, the vent-30 bricks placed in the valve block will control the drive cylinder again according to the prevailing pressure range. The return movement of the drive cylinder operates quickly as a normal double-acting cylinder. In the return movement, the piston of the pressure relief cylinder first returns and then the piston of the drive cylinder starts to move. In this case, the pressure chuck-35 ink cylinder is made to operate rapidly back and forth if the reinforcement distance achieved at one time is insufficient.

10

Next, the theoretical forces and velocities of the drive cylinder are calculated from the application example. The calculations are based on a maximum system pressure of 180 bar at a flow rate of 40 rpm. Here, the piston diameter of the drive cylinder is 50 mm with the piston-5 shaft having a diameter of 35 mm. Correspondingly, the piston rod diameter of the booster cylinder is 32 mm. The pressure increase factor then becomes 2.44. In addition, the stroke length of the booster cylinder is 240 mm, while the stroke length of the drive cylinder is 680 mm. With these values, a force of approximately 1700 kg is achieved during a rapid stroke and a forward stroke of 0.98 s is achieved. Similarly, a force of approximately 3500 kg is obtained during a stroke and a 2.00 s stroke of the forward stroke. At a pressure of 440 bar 15, a force of about 8600 kg is achieved. Accelerated movement accelerates the total labor movement by one third. In other words, with the return movement lasting about one second, the total movement in the fast motion takes about two seconds, while the basic movement takes about three seconds. In practice, the illustrated system is three speed 20 and powerful and automatically adjusts to the load. The rapid movement speed was in the pressure range of 0-130 bar, with a force of 0-1700 kg. Normal travel speeds operate within a pressure range of 130 to 160 bar, with an available force of 1700 to 3500 kg. The third speed operates during pressure increase 25. In this case, the pressure range is 160 to 440 bar with an available force of 1700 to 8600 kg. Based on the foregoing, a force equivalent to conventional 75 mm piston diameters is achieved with a piston diameter of 50 mm. Even with a quick motion, the reciprocating motion of a larger-split-member cylinder would take five seconds, whereas, according to the invention, it would be only two seconds. On the other hand, by increasing the piston diameter of the drive cylinder by 75 mm, a force of 8000 to 16000 kg would be obtained by the system described.

In addition to certain types of components, their dimensioning is essential to the operation of the system. With the above values, oil is flowing through connection D2 at 40 rpm and in the return flow at 80 rpm. A 3/4 "hose is connected to this connection. Oil is flowing through the connection D1 at a work rate of 20 rpm and a return flow of 40 l / min. A 1/2" hose is connected to this connection. Due to the increased pressure, a thick-walled conductor pipe with an inner diameter of 15 mm is connected to the connection U2 at the compound-5. Similarly, a thin-walled conductor tube with an inside diameter of 12 mm is sufficient for connections B2 and UI. Further, the connection port 36 of the supply line 16 of the drive cylinders 14 is made open so that a large amount of oil during the return movement can flow without unnecessary throttling. In other words, the system has small pressure losses due to properly dimensioned piping and flow openings.

Above described is a system using oil as a pressure medium, which is also suitable for pneumatics or water hydraulics. In addition to the hydraulic splitter, the system can be applied to other long and fast work movements, but also occasionally to heavy-duty applications. These include presses and actuators for large valves. In addition, the system may replace existing devices having two or more drive cylinders. Now, in the system of the invention, the accelerator movement of the drive cylinder works, although a booster cylinder is also available. Due to the additional force obtained by the pressure increase cylinder, the piston diameter of the drive cylinder can be kept advantageously small. In this case, the movement of the drive cylinder remains fast and still faster at high speed.

Claims (11)

12 1. Pressure medium system including pressure medium source (15), 5. double-acting actuator cylinder (14) including feed line (16) and return line (17), - directional valve (18) for controlling actuator cylinder (14), - pressure medium conduits (19) combined with pressure medium source through the directional valve (18) to the drive cylinder (14) 10 and back, the pressure boost cylinder (21) disposed between the directional valve (18) and the supply line (16) of the drive cylinder (14), and the directional valve (18) and pressure boost cylinder (21) a pressure-controlled sequence valve (22) disposed between the 15 and connected to the pressure-raising cylinder (21) such that when the pressure rises above the setpoint of the pressure-controlled sequence valve (22) on the supply line (16), 21) for increasing the power of the connected driving cylinder (14), characterized in that: e this pressure medium system further includes a pressure-controlled check valve (35) connected to the feed line (16) and the return line (17), adapted to prevent escalation of the elevated-25 pressure to the feed line (16) when q pressure-controlled sequence valve (22) a pressure-controlled quick-action valve (20) arranged between the directional valve (18) and the drive cylinder (14) to circulate the pressure medium from the return cylinder operating line x £ 30 (17) to the feed line (16) to increase the operating speed of the drive cylinder (14); o with the brick (22) and the booster cylinder (21), three pressure-controlled movement velocity and force ranges are formed in the pressurized fluid system, and 13 - a valve block (23) with a pressure-controlled quick-action valve (20), a pressure-controlled sequence valve (22) a check valve (35) is provided. The pressure medium system according to claim 1, characterized in that the directions of movement of the drive cylinder (14) and the pressure boosting cylinder (21) are arranged opposite. The pressure medium system according to claim 1 or 2, characterized in that the drive cylinder (14) and the pressure boosting cylinder (21) are arranged substantially parallel and fixed to each other. Pressure medium system according to one of Claims 1 to 3, characterized in that the pressure-controlled sequence valve (22) is set to be 5-20%, more preferably 10-15% lower than the maximum pressure of the pressure medium source (15). Pressure medium system according to one of Claims 1 to 4, characterized in that the valve block (23) is supported or integrated in the pressure boosting cylinder (21). The pressure interstage material system according to any one of claims 1 to 5, characterized in that the drive cylinder (14) has a strong wall. Pressure medium system according to one of Claims 1 to 6, characterized in that the pressure boosting cylinder s1 (21) consists of a low pressure part (28) and a high pressure part (29) x 30 which are connected end-to-end by a spacer (30). ). LO CO LO 05 Pressure medium system CM according to claim 7, characterized in that the low pressure part (28) comprises a piston (31) 35 provided with a piston rod (32) sealed in the spacer (30) and arranged as a functional piston. 14 A pressure medium component adapted to be connected to a pressure medium system comprising: - a pressure medium source (15), a dual-acting actuator cylinder (14) including a feed line (16) and a return line (17), a direction valve (18) for controlling the actuator cylinder (14); 10 - pressure medium conduits (19) connected from the pressure medium source (15) through the directional valve (18) to the drive cylinder (14) and back, and the pressure medium component is a pressure boost cylinder (21) adapted to be mounted on the directional valve (18) and actuator (16), and the pressure medium component includes a pressure-controlled sequence valve (22) connected to the pressure-raising cylinder (21) such that when the pressure in the supply line (16) of the drive cylinder (14) exceeds the pressure-controlled sequence valve (22) pressure medium for the booster cylinder (21) the booster cylinder n (21) for increasing propulsion coupled to the drive cylinder (14), characterized in that the pressure medium component further comprises a pressure-controlled check valve (35) adapted to be connected to the feed line (16) and the return line (17). o C'J in the situation where the pressure-controlled sequence valve (22) has changed its position, o - the pressure-controlled high-speed valve (20) arranged between a. 30 directional valve (18) and the actuating cylinder (14) to circulate the pressure CL from the return cylinder LO g (17) to the feed line (16) to increase the operating speed en g of the driving cylinder (14) so that, together with the pressure-controlled sequence valve (22) and the booster cylinder (21), the pressure medium system comprises three pressure-controlled - and the power range, and 15 valve blocks (23) into which the pressure-controlled rapid movement valve li (20), a pressure-controlled sequence valve (22) and a pressure-controlled check valve (35) are provided. Hydraulic splinters comprising a body (10) and a splitting blade (12) therein, and a buffer (11) for actuating a pressurized fluid system, characterized in that the pressurized fluid system is according to any one of claims 1 to 8. 10 Hydraulic splinters according to Claim 10, characterized in that the drive cylinder (14) and the pressure boosting cylinder (21) belonging to the pressure medium system are fixed to each other and arranged inside the buffer (11). δ c \ i 0 X CC CL LO LO CO LO 01 o o CM 16