DE70246T1 - HYDRAULIC BLOCKING DEVICE. - Google Patents

Abstract

1. A percussion apparatus moved by a pressurised fluid, of the type comprising a mobile striking mass (2) in the form of a piston supplying a series of impacts on a tool (3), this piston being slidably mounted in a cylinder (4) which, provided in the body (5) of the apparatus and including ports (6, 7) connected by ducts (8, 9), serves additionally in the sliding of a distributor (10) connecting the chamber (11) situated above the piston alternately to a high pressure circuit (12), for enabling the piston to descend rapidly, and to a low pressure circuit (13) for effecting the return strocke of this piston, characterised in that it comprises, on the one hand, a non-return valve (22) enabling fluid to pass from the chamber (11) located above the strike piston towards the high pressure circuit (12) and, on the other hand, means ensuring that the distributor (10) is displaced sequentially in such a way that, starting from a position in which the chamber (11) located above the piston is connected to the high pressure (12), the distributor is displaced very rapidly as far as a position in which it interrupts the connection between the said chamber and the high pressure, then at a lower, controlled speed, so as to delay the connecting of the chamber (11) to the low pressure circuit (13), so as to enable the maximum amount of restorative energy to be recovered for the entire duration of the isolation of the chamber located above the piston with respect to the high pressure and low pressure circuits, by compressing the fluid isolated in the chamber for the passage of the latter into the high pressure circuit by means of the non-return valve.

Claims (1)

Claims 1. ii with pressure medium acted upon impact device, the one bew2glichG impact mass in the form of a successive Contains strokes on a tool Kolbon exercising in a formed in the device body and via channels connected openings having cylinder is guided, which also leads a manifold, the one above the Piston arranged chamber alternatively with a high pressure circuit for performing a rapid downward movement of the Piston and brings in connection with a low pressure circuit for executing the piston return stroke, characterized in that that on the one hand there is the medium from above the impact sleeve arranged chamber to the high pressure circuit (12) permeable Non-return valve (22) and, on the other hand, contains means which ensure a subsequent shift of the distributor (10), such that starting from a position in which the chamber (11) arranged above the piston with the ! Punch pressure (12) is connected, the distributor moves very quickly to a position in which it closes the connection this chamber and the high pressure separates, and then with reduced and controlled speed so shifted, that the establishment of the connection of the chamber (11) with the low-pressure circuit (13) is delayed to during the entire The duration of the isolation of the chamber arranged above the piston from the high-pressure and low-pressure circuits maximum recovery of the restitution energy to be achieved by removing the medium isolated in the passage chamber from this is pressed into the high pressure circuit via the non-return valve. 2. Impact device according to claim 1, characterized in that the displacement time of the distributor (10) between the closure the connection between the chamber (11) arranged above the piston and the high-pressure circuit (12) and the connection between these Chamber (11) with the low-pressure circuit (13) is equal to the time required for the strongest rebound that is in operation of the hardest rock known. 3. Impact device according to claim 1 or 2, characterized in that the distributor (10) experiences a new acceleration movement, as soon as the chamber (11) located above the piston is in connection with the low-pressure circuit (13), so that this opening is largely released and a free movement of the movable impact mass (2) is possible. 4. Impact device according to one of claims 1 to 3, characterized in that that the distributor (10) has two areas with different sectional shape, namely one on the piston side Area (16), the sectional shape of which corresponds to that of the cylinder (4), in which the percussion piston (2) is arranged in a guided manner is, and a region facing away from the piston with a larger Sectional shape which is arranged in a cavity (18) which extends the cylinder and has a larger sectional shape than the distribution area has a larger sectional shape, wherein the distribution area with a larger sectional shape into a chamber (19) the same sectional shape can penetrate between the cylinder (4) and the enlarged cavity (18) is arranged, the penetration into this chamber (19) begins when the distributor (10) reaches a position in which it establishes the connection between the chamber arranged above the piston (11) and the low-pressure circuit (12) closes, and that through the chamber (19) with a medium sectional shape and the limited transition between the two distribution areas Annular volume with the chamber arranged above the piston (11) is in communication via at least one passage (20). 5. Impact device according to claim 4, characterized in that the escape of the medium from the annular chamber (19) enables Passage (20) in which the annular chamber delimits the outside Wall is arranged. ■ δ. Striking device according to claims 3, 4 and 5, thereby gekenrizeichhetj that the distributor (10) between the two cylindrical Areas (16, 17) of different sectional shape has a groove (35) and that at least one channel (36) opens into the cylinder (4), through which the through the groove (35) limited ring volume can be connected to the low-pressure circuit as soon as the position of the distributor (10) disconnects the above the piston arranged chamber (11) with the Ensures low pressure circuit. 7. Impact device according to claim 4, characterized in that Ln distributor (10) a channel (25) is arranged axially, whose in the annular surface (23), which the distribution areas of different Sectional shape connects, the opening end forms a calibrated opening that allows the medium to escape the annular chamber ensures. u * impact device according to claims 3, 4 and 7, characterized in that the chamber (19) in which the compression of the liediums takes place in the course of the distribution movement, a Forms circumferential slit (37), which can be brought into connection with the low-pressure circuit via a channel (38) loaded in the distributor as soon as its position connects the Chamber (11) with the low-pressure circuit located above the piston ensures *