FR2873397A1 - Post driver device, has movable mass that knocks head of post for assuring its embedding in ground, and safety valve that stops activation of movable mass in descent, when clamp system is in open position - Google Patents

Abstract

The device has a movable mass guided on a vertical post and that knocks the head of a post for assuring its embedding in the ground. The movable mass is activated by an operating unit constituted by a cable which is wound on pulleys. The cable assures lifting and descending of the movable mass. A safety valve (15) stops the activation of the movable mass in descent, when a clamp system is in open position.

Description

1 2873397

  The present invention relates to push-in devices of the type comprising a moving mass guided on a vertical mast and actuated by operating means, which operating means are able to ensure the lifting of said moving mass along said vertical mast, as well as its descent, in order to hit the head of the pile to allow its insertion into the ground, and two movable arms forming a gripper system, associated with actuating means, which actuating means are adapted to confer on said system of clamp, on the one hand an open position, and on the other hand a closed position, tight on the pile being driven.

  In the current driving devices of this type, the means for operating the mobile mass generally consist of a cable actuated by a first hydraulic cylinder, and the pile clamp, formed by the two movable arms, is actuated by a second hydraulic cylinder. The mass cylinder and the clamp cylinder are controlled by the levers of a hydraulic distributor, depending on the type of action desired.

  Conventionally the mass is actuated downhill only to hit the head of the pile in order to ensure its insertion into the ground. But the handles of the hydraulic distributor can be manipulated unexpectedly or involuntarily, especially in the direction of a descent of the moving mass, which can be dangerous for the operator, or for any other person, especially if the system clamp is in the open position.

  The present invention aims to improve the safety of this type of enfoncepieux. For this purpose, the driving device according to the invention comprises means capable of preventing downward actuation of the moving mass when the gripper system is in the open position.

  According to a particularly advantageous embodiment, the means for actuating the moving mass consist of a cable associated with a raising and lowering ram, this jack, called a mass ram, being equipped with a safety valve controlled by open and / or closed position indicator means of the gripper system, this safety valve being able to prevent the actuation of said mass ram in the direction of a descent of said moving mass when the gripper system is in the open position.

  Preferably, the mass cylinder consists of a jack of the simple effect type whose chamber, once in pressure, ensures the raising and the high position of the moving mass, and whose chamber, once in depression, determines the lowering and the low position of said moving mass, the pilot-operated safety valve associated with said ground ram being adapted to prevent the depression of said cylinder chamber when the gripper system is in the open position.

  The mass ram is preferably a hydraulic cylinder associated with a hydraulic valve type safety valve, controlled hydraulically or electrically.

  In this context, the safety valve is advantageously in the form of a controllable check valve. This valve is arranged, in the rest position, firstly to allow the oil supply of the cylinder chamber, and secondly to prevent the oil outlet of this chamber; in addition, it is able to be activated to allow the passage of oil in both directions when the gripper system is in the closed position.

  This allows in particular to prevent the descent of the mass in case of absence of current, in the case where the valve is electrically controlled.

  According to a particular embodiment, the safety valve is of the electric control type, controlled by an activated electric switch when closing the clamp system.

  The gripper system can then be manually operated, or controlled by a hydraulic cylinder.

  According to another embodiment, the gripper system of the pile driver device is operated by a double-acting hydraulic cylinder provided with a chamber whose pressurization ensures the clamping of said clamp system, said clamping chamber, and of a chamber whose pressurization ensures the opening of said clamp system, said opening chamber; in addition, the driving device also comprises a hydraulic safety valve type hydraulic control, associated with the mass cylinder and connected to the hydraulic supply line of the clamping chamber of the clamp cylinder.

  In this case, the pressurization of the hydraulic supply pipe of the gripping chamber of the clamp cylinder acts on the safety valve so as to allow the actuation of the mass ram in the direction of a descent of the mobile mass; on the other hand, the absence of oil pressure in this pipe prevents the corresponding descent actuation.

  The invention will now be illustrated, without being limited in any way, by the following description of several particular embodiments, given solely by way of example and represented in the appended drawings in which: FIG. 1 is a simplified view, in perspective a driving device to which the invention applies, the moving mass being here in the upper position and the gripper system in the open position; FIG. 2 is a view of the pile driver device of FIG. 1 with the moving mass in the down position and the clamp system closed; FIG. 3 is a partial perspective view of a first possible embodiment of the securing system according to the invention applied to the driving device of FIGS. 1 and 2, the hydraulic safety valve of the mass ram being here hydraulically driven; FIG. 4 corresponds to the hydraulic diagram of the driving device of FIG. 3; FIG. 5 is a hydraulic diagram of another possible embodiment of a secure driving device according to the invention; hydraulic safety valve of the mass cylinder being electrically controlled; Figures 6 and 7 show a possible embodiment of the clamp system, respectively seen in the closed position and in the open position, in the context of a secure driver device as illustrated in Figure 5; FIGS. 8 and 9 show another possible embodiment of the gripper system, of the manually operated type, seen respectively in a tight and open position, in the context of a pile driver whose ground jack is secured by an electrically controlled valve.

  The pile driver illustrated in Figures 1 and 2 comprises a vertical mast 1 on 20 which is guided a moving mass 2 intended to hit the head of a pile (not shown) to ensure its insertion into the ground .

  The moving mass 2 is actuated by operating means 3 able to ensure its raising and lowering violently. These operating means 3 consist of a cable 4 wound on two pulleys placed at the ends of a compass 5 actuated by a hydraulic jack 6, hereinafter referred to as mass ram. This mass cylinder 6 is here a single-acting cylinder comprising a single chamber. The extension of its rod ensures the lifting of the mobile mass 2, and its removal inside the body causes the lowering of the mass 2.

  The base of the mast 1 is equipped with a clamp system 10 consisting of two movable arms 11 and 12 associated with actuating means here in the form of hydraulic cylinder 13 (visible only in Figure 2).

  This jack 13, hereinafter referred to as clamp cylinder, is of double-acting type; the extension and the withdrawal of its rod respectively ensure the closing and opening of the gripper system 10. The clamp 10 is clamped on the pile during the downward actuation of the moving mass 2 to ensure the vertical maintenance of this pile and its correct guidance, when driving into the ground.

  4 2873397 The base of the vertical mast 1 is provided with securing means on a suitable support of a transport vehicle, in particular on the three-point linkage system of an agricultural tractor.

  Both hydraulic cylinders 6 and 13 are powered by a suitable hydraulic circuit, for example the hydraulic circuit of the agricultural tractor carrier. Their actuation is conventionally managed by means of the control levers of a hydraulic distributor, not shown in FIGS. 1 and 2. In a usual manner, the corresponding distributor also manages other controls of the driver, for example the actuation of lifting cylinders, pivoting, or lateral extension of the operating compass.

  In Figure 1, the moving mass 2 is shown raised, and the clamp system 10 is in the open position; in Figure 2, the mass 2 is in the lowered position and the clamp system 10 is in the closed position.

  In accordance with the invention, the driving device of FIGS. 1 and 2 is equipped with means which are adapted to prevent downward actuation of the moving mass 2 when the gripper system 10 is in the open position, ie say when the space under said mass 2 is released.

  Accordingly, in the context of the representation of Figure 1, wherein the clamp system 10 is in the open position, the corresponding means prohibit the actuation of the jack 6 to lower the mass 2.

  This prevents any risk of inadvertent actuation of the mass 2 while the operator or other people would be under the striking space released by the two movable arms 11 and 12.

  For this purpose, and as illustrated in FIGS. 3 and 4, the ground jack 6 is equipped with a safety valve 15 in the form of a controlled non-return hydraulic valve, placed on its supply line 16.

  In the rest position, this non-return valve 15 allows the oil supply of the chamber of the mass cylinder 6, and it prevents the oil outlet of this chamber. In addition, this valve 15 is connected to the supply circuit of the clamp cylinder 13 so as to ensure its hydraulic activation (allowing the passage of oil in both directions), only when the clamp system 10 is in the closed position . In Figures 3 and 4 it is noted that the clamp cylinder 13 is a double-acting cylinder; its chamber 17 (called the clamping chamber), once under pressure, closes the clamp system 10, and its other chamber 18 (called the opening chamber), once under pressure, ensures the opening of the clamp system 10.

  2873397 The aforementioned hydraulic control is achieved through the oil line 20 which connects the valve 15 to the hydraulic pipe 21 supplying the clamping chamber 17 of the clamp cylinder 13.

  It is therefore understood that, once in the high position, the moving mass can be actuated downhill only when the chamber 17 of the cylinder 13 is in pressure, that is to say in the case where the system of clip 10 is closed.

  FIGS. 3 and 4 show the hydraulic distributor 22 which controls the operation of the hydraulic cylinders 6 and 13. In a conventional manner, this distributor 22 is supplied with oil by a hydraulic pump 23 from a reservoir 24. A filter 25 and a strainer 26 are arranged in a conventional manner upstream and downstream of the tank 24.

  A first pressure limiter 27 is integrated in the hydraulic distributor 22; a second pressure limiter 28 can be placed on a pipe 29 connecting the chamber 17 of the cylinder 13 and the reservoir 24 to allow the clamp 10 to adapt to the configuration of the pile, and in particular to absorb any variation of diameter linked for example to the presence of nodes.

  According to another possible embodiment, the mass cylinder can be equipped with a hydraulic safety valve of the electric control type, controlled by an electric switch arranged at the gripper system.

  An example of a corresponding embodiment is illustrated in FIG.

  The hydraulic diagram of this Figure 5 is very similar to that of Figure 4, and there are the same main bodies namely the mass cylinder 6 and the double clamp effect cylinder 13, connected to the distributor 22; but the safety valve 15 hydraulically controlled in the previous embodiment is here replaced by a valve 15 'electrically controlled.

  This hydraulic valve 15 'is controlled by an electric switch 30 activated when closing the clamp system of the driver.

  The means for indicating the open and / or closed position of the gripper system are different from the previous embodiment (illustrated in FIGS. 3 and 4), but for the rest, the operation of the device is identical.

  FIGS. 6 and 7 illustrate, in plan view, the gripper system 10 capable of equipping the pile driver device illustrated in FIG. 5.

  In these two figures, it is noted that the two movable arms 11 and 12 are operated simultaneously in rotation by means of the hydraulic cylinder 13, this by means of mechanical means 31 of the spring type toggle. This toggle allows the two clamping arms 11 and 12 to accommodate the dimensions and shapes of the pile; its presence makes it possible to dispense with the pressure limiter 28 mentioned above.

  The movement of the cylinder rod 13 causes the activation or deactivation of the electric switch 30, depending on whether the clamp system 10 is closed (Figure 6) or open (Figure 7).

  In particular, the switch 30 is advantageously activated when the clamp system 10 is in the closed position. This activation drives the safety valve 15 'so that the latter allows the flow of oil in both directions, so as to allow the actuation of the mass cylinder 6 lifting and lowering.

  On the other hand, when the gripper system 10 is in the open position (FIG. 7), the electric contactor 30 is not activated and the controlled nonreturn valve 15 'prevents the oil outlet from the ground jack 6, and is prohibited. as a result the descent of the moving mass 2.

  The use of an electrically controlled valve 15 'makes it possible to equip the driving device with a clamping clamp 10 of the manually operated type. FIGS. 8 and 9 illustrate this type of manually operable gripper, in the closed position in FIG. 8, and in the open position in FIG. 9. In this gripper system 10, the two movable arms 11 and 12 are simultaneously actuated by the toggle joint at spring 31, by means of the handle 32, this according to the needs.

  The actuation of the operating handle 32 deactivates the electric switch 30 as soon as the clamping device 10 is started.

  In all cases, the hydraulic safety valve with hydraulic or electrical control is of conventional structure and it is selected from the available models, depending on the desired features.

  The presence of the technical means in accordance with the present invention makes it possible to substantially increase the safety of the driven pile driver devices.

7 2873397

Claims (9)

- CLAIMS -   1.- Pusher device comprising: - a movable mass (2) guided on a vertical mast (1) and actuated by operating means (3), which operating means (3) are able to ensure the lifting of said movable mass (2) along said vertical mast (1), as well as its descent, for striking the head of the pile to allow its insertion into the ground, and - two movable arms (11, 12) forming a system of clamp (10), associated with actuating means (13, 32), which actuating means (13, 32) are adapted to impart to said gripper system (10), on the one hand an open position, and d on the other hand a closed position, clamped on said pile during driving, characterized in that it comprises means (15, 20; 15 ', 30) capable of preventing the descent of the moving mass (2 ) when the gripper system (10) is in the open position.   2.-Pusher device according to claim 1, characterized in that the actuating means of the movable mass (2) consist of a cable (4) associated with a lifting jack and lowering (6), said cylinder of mass, said mass cylinder (6) being equipped with a safety valve (15, 15 ') controlled by means (20, 30) indicating the open and / or closed position of the gripper system (10), which safety valve (15, 15 ') is able to prevent the actuation of said mass cylinder (6) in the direction of a descent of said moving mass (2) when said clamp system (10) is in the open position .   3.-Pusher device according to claim 2, characterized in that the mass cylinder (6) consists of a jack of the single-acting type, the chamber, once in pressure, ensures the lifting and the high position of said movable mass (2), and whose chamber, once in depression, determines the lowering and lower position of said moving mass (2), the piloted safety valve (15, 15 ') associated with said cylinder (6) being adapted to prevent depression of said cylinder chamber when the clamp system (10) is in the open position.   4.-Pusher device according to any one of claims 2 or 3, characterized in that the mass cylinder (6) consists of a hydraulic cylinder associated with a safety valve type hydraulic valve (15, 15 ') , controlled hydraulically or electrically.   5.- Pusher device according to claim 4, characterized in that it comprises a safety valve (15, 15 ') in the form of a controllable check valve, which valve is arranged, in the rest position, on the one hand for allowing the supply of oil to the chamber of the mass cylinder (6), and secondly to prevent the oil from escaping from said chamber, and which valve (15, 15 ') is capable of being activated for allow the passage of oil in both directions when the gripper system (10) is in the open position.   6. Driver-driving device according to any one of claims 2 to 5, characterized in that it comprises a safety valve (15 ') of the electric control type, controlled by an electric switch (30) activated during closing the clamp system (10).   7.- Pusher device according to claim 6, characterized in that it comprises a gripper system (10) manually controlled (32).   8.- Pusher device according to claim 6, characterized in that it comprises a clamp system (6) controlled by a hydraulic cylinder (13).   9.- Pusher device according to any one of claims 2 to 5, characterized in that it comprises a clamp system (10) operated by a double-acting type hydraulic jack (13), said clamp cylinder, equipped with a chamber (17) whose pressurization ensures the clamping of said gripper system (10), said clamping chamber, and - a chamber (18) whose pressurization ensures the opening of said system clamping device (10), said opening chamber, and in that it comprises a hydraulic control type hydraulic safety valve (15), connected to the hydraulic pipe (20) supplying the clamping chamber ( 17) of said gripper system (13).