Untitled record

The invention relates to a high-pressure piston compressor, to the hydraulic drive piston on each of its end faces ever a coaxially arranged compressor piston is connected, and in which the drive of the drive piston is effected by a continuously variable pump, the liquid blowing agent under the action of a with an auxiliary slide equipped control slide alternately on one of the two sides of the drive piston, in particular for generating the highest gas pressures, for example those of over 1500 kg (cm 2, the drive piston is on both sides each provided with a brake piston, which dips at the end of the stroke in a brake cylinder and displaces the medium contained in the brake cylinder via brake slots.

It is known in reciprocating piston engines to take measures to mitigate the impacts occurring near dead center. As a means of mitigating such shocks, magnetic and pneumatic brakes as well as mechanical springs have been used primarily in lower power and lower working pressure reciprocating compressors. It is also known to reduce the aforementioned impacts in the dead center by plungers which dip at the stroke end in corresponding brake cylinder and displace the medium contained in these via brake slots or other throttle channels. In all these constructions, the kinetic energy of the compressor piston system braked at the stroke end is only destroyed without making it usable within the scope of the overall system of the reciprocating compressor.

The invention aims at a further development of the high-pressure piston compressor of the type indicated at the outset with the aim of using the resulting in a known brake cylinder pressure not only to brake the working or driving piston, but at the same time to actuate an auxiliary slide. This is done according to the invention in such a way that each of the two brake cylinders is connected via respective pipes with one side of the auxiliary slide.

The invention will be explained in more detail with reference to the drawing of an embodiment. It shows F i g. 1 is a schematic sectional view of the high-pressure piston compressor according to the invention with hydraulic braking of the drive piston and hydraulic reversal of the auxiliary slide and F i g. 2 is a diagram which shows the timing of the movements of the driving piston with its two compressor pistons and of the auxiliary and control slide.

According to F i g. 1 runs in the hydraulic drive cylinder 1, which is closed at its front ends by the cylinder cover 2, 2 ', the driving piston 3. On both sides of the drive piston with brake piston 4, 4' rigidly connected, which provided with brake slots 5, 5 ' are. The brake cylinders 6, 6 ', which represent protuberances of the cylinder cover 2, 2', together with the brake piston 4, 4 'brake chambers 7, 7'. The compressor cylinders 8, 8 'are closed with cylinder covers 9, 9', in which the intake valves 10, 10 'and the outlet or pressure valves 11, 11' are located. In the compressor cylinders run the compressor piston 12, 12 ', which either consist of the drive piston 3 in one piece or are used on one side fixed in the latter.

In the slide housing 13 of the spool 14 and the auxiliary slide 15 are housed. 16, the pressure chamber is designated inside the valve body. The connection channels 17,17 'serve the supply of the control pressure means for adjusting the auxiliary slide 15; the connection channels 18, 18 'serve to supply the control pressure means for adjusting the control slide 14.

With 19 is driven by the motor 20, continuously variable delivery pump for the hydraulic fluid referred to. The pump 19 draws in via the line 21 liquid from the reservoir 22 and pushes them by means of the line 23 into the pressure chamber 16 of the valve body 13. In the branched off from the pressure line 23 reflux line 24 is the druckdruckventi125 arranged. The lines 26,26 'serve to supply the pressure fluid from the spool to the drive cylinder. 1 The return lines 27, 27 'lead from the spool to the reservoir 22. The lines 28, 28' make the connection from the brake chambers 7, 7 'to the connection channels 17, 17' of the auxiliary slide 15 ago. The lines 29, 29 'convey the forwarding of the control pressure from the auxiliary slide 15 to the spool 14. With 30, 30' connecting lines between the lines 28 and 26 or 28 'and 26' are referred to, in which check valves 31, 31 'are arranged. In the outgoing of the pressure line 23 branch lines 32, 32 ', the starting valves 33, 33' are arranged.

To start up the high pressure piston compressor, the feed pump 19 is started. Since the driving piston 3, the auxiliary slide 15 and the spool 14 can be in any position, the compressor does not always start. For this purpose, for example, the starting valve 33 'is opened, whereby the auxiliary slide 15 in the from F i g. 1 apparent position is brought. The auxiliary slider 15 controls the spool 14 in the from F i g. 1 apparent position, since the space to the left of the spool 14 is pressurized. Thus, hydraulic fluid is supplied via the line 26 'in the right side of the driving cylinder 1, and the driving piston 3 moves further to the left. In this case, when the brake piston 4 enters the brake cylinder 6, then the pressure of the trapped in the brake chamber 7 liquid, and this flows back through the brake slots 5. As a result, the pistons 3,12,12 'partially decelerated. Upon further immersion of the brake piston 4 in the brake cylinder 6, the brake slots 5 are covered, and it increases the pressure in the brake chamber 7 via the pressure prevailing in 23, 16, and 26 '. This pressure is shared by the channel 28 with the channel 17, whereby the auxiliary slide 15 is thrown to the right and the pressure chamber 16 via the line 29 'with the - connecting channel 18' connects. As a result, the spool 14 goes to the left, because the space left of the spool 14 via port 18, line 29 and the corresponding channels of the valve body 13 is connected to the reflux line 27, so the space left of the spool 14 has become de-pressurized. By this position of the spool 14, the pressure chamber 16 is connected via the line 26 to the left side of the cylinder of the drive piston 3. At the same time the brake chamber 7 is connected to the pressure chamber 16 via the check valve 31. Now pushes the Druckfiüssigkeit via line 23 and pressure chamber 16, the driving piston 3 in the direction to the right. Before reaching the right turnaround is analogously the same game, the auxiliary slide 15 and the spool 14 are again in the from F i g. 1 apparent position brought, and the pistons 3, 12, 12 'run back to the left. With 23 a, a pressure accumulator in the pressure line 23 is referred to, which receives the amount of oil @, which during the passage of the spool 14 through the zero position no unhindered flow, so that the operation can be made economical.

The in F i g. 1 illustrated high-pressure piston compressor thus has a completely hydraulic control. The number of strokes of the drive piston 3 and thus the compressor piston 12,12 'can be adjusted arbitrarily by volume control using the continuously variable feed pump 19. The resulting in the brake cylinders 6, 6 'after immersion of the brake piston 4, 4' pressure is thus not only used to decelerate the drive piston 3, but at the same time to actuate the auxiliary slide 15.

F i g. 2 shows from top to bottom the timing of the movements of the auxiliary slide 15, the spool 14 and the driving piston 3 with its two compressor pistons 12, 12 '. The abscissa is the time t of a piston movement of 3,12,12 'from the right R and left L and back to the right, so a whole back and forth movement of the piston applied. The ordinates are the respective slide and piston paths, wherein the lines 15-15, 14-14 and 3-3 indicate the respective center positions of the auxiliary slide 15, the spool 14 and the driving piston 3.

At 61, the driving piston 3 starts from the right turning point. At this time, the Hifsschieber 15 is left and the spool 14 right. When the driving piston 3 has arrived at 62, then the brake piston 4 immersed in the brake cylinder 6, and the braking of the driving piston 3 begins. After covering the brake wire 5 by the edge of the brake cylinder 6, that is, at 63, liquid is pressed via the Anschlußkana117 to the left side of the auxiliary slide 15, and the auxiliary slide 15 goes to the right. If the auxiliary slide 15 has exceeded its middle position at 64, the control slide 14 is controlled rapidly from right to left. When the spool 14 goes over its center position at 65, then receives the left driving cylinder side of the driving cylinder 3 via line 26 hydraulic fluid, and the driving piston 3 is pushed from left to right. At position 66, the same game begins with the opposite moves.

In the high-pressure piston compressor according to the invention, therefore, the movements of the drive piston are braked hydraulically in the reversal points. The auxiliary slide is automatically reversed hydraulically, whereby the spool is brought very quickly hydraulically in its other end position. Also, the auxiliary slide and the spool are hydraulically caught in their outer layers. With the help of the starting valves, the compressor can be started from any position. Due to the infinitely variable feed pump, any desired number of strokes of the drive piston and thus the compressor piston can be adjusted manually or by a regulator.