A CONCRETE WORKING MACHINE

Description

Technichal field

[0001] This invention relates to a concrete working machine for working a concrete surface, comprising a carrier with a transverse feed beam that carries a carriage with a water jet nozzle, a first hydraulic motor for moving the carriage along the feed beam, a second hydraulic motor for pivoting the nozzle about a first axis so as to give it an attack angle to the concrete in both directions when the carriage are reciprocated in working sweeps, and a third hydraulic motor for pivoting the nozzle about a second axis for oscillating it in a plane transverse to the feed beam.

Background of the invention

[0002] Road salting has a detrimental influence on concrete road beds, and the surface layer of road beds of concrete bridges must be replaced after some years before the salt has penetrated down to the steel reinforcement; otherwise will the maintenance costs be very high. Therefore, one wants to remove the upper eroded concrete layer to free the uppermost reinforcement layer and to cast a new concrete surface layer before the uppermost reinforcement layer has been affected by the salt. Machines for such concrete removal are known for example by SE-451742-B, US-5361993-A, WO 0231265, and SE-508821-C. The working unit of such machines, that is, the feed beam with its carriage, is in a difficult environment because of the splatter of rock, concrete and water, and sensors and electric lines for control are particularly at risk.

Object of invention and brief description of the drawings

[0003] It is an object of the invention to improve the reliability and the availability of a concrete working machine of this kind.

Brief description of the drawings

[0004] 

Figure 1 is a perspective view of a concrete working machine that is shown as an example of the invention.

Figure 2 is a perspective view of a portion of the machine shown in figure 1.

Figure 3 is a schematic view of the portion shown in figure 2 in operation.

Figure 4 is a diagram of the control system for the machine shown in figures 1-3.

Description of the illustrated example of the invention.

[0005] Figure 1 shows a concrete working machine that comprises a mobile unit; a vehicle 11 on wheels that carries a foldable arm 13,14. Built-in hydraulic motors 12 in the wheels are arranged to move the vehicle. The vehicle has a power unit that comprises a motor that drives a hydraulic pump. Water is stored in a separate container which has a high-pressure water pump. The foldable arm has an inner arm 13, which is mounted on the vehicle to be turnable about an axis parallel with the longitudinal axis of the vehicle, and an outer arm 14, which is mounted on the outer end of the inner arm about an axis that is also parallel with the longitudinal axis of the vehicle. The inner arm consists of two parts, longitudinally displaceable relative to each other so that the inner arm is extensible: The outer end of the outer arm carries a transverse feed beam 15 that is also turnable about an axis parallel with the longitudinal axis of the vehicle. The feed beam can thus be displaced laterally and it can also be used for vertical surfaces. A carriage 20 is mounted on the feed beam to be movable along it. The feed beam and the carriage is the working unit of the machine. The carriage is shown separately as figure 2 and it is movable as indicated with the arrows 19 in figure 2. The carriage 20 has a hydraulic motor 21 that has a drive gear in engagement with a gear rack on the feed beam for driving the carriage along the feed beam. The carriage carries a tube 22 that has a nozzle 23 at its end and it is coupled to the pump for high pressure water so that the nozzle will eject a laminar water jet at supersonic speed that can work concrete. The tube 22 with its nozzle 23 can be regarded as the nozzle. A hydraulic motor 24 is built together with a bearing housing 25 for a crank shaft so that the motor via the crank shaft will oscillate the tube 22 about an axis II in a plane transverse to direction of movement of the carriage. A hydraulic motor in the form of a hydraulic cylinder 26 is coupled to swing the tube 22 together with the motor 24 and the bearing housing 25 about an axis I that is transverse to the direction of movement of the carriage, that is, to pivot the tube in a plane parallel with the with the feed beam. The tube with its nozzle projects into a slot in a shield 28 that keeps within it the splashing water and the concrete particles broken away from the concrete surface.

[0006] Figure 3 shows schematically the carriage 20 and the tube 22 during a working operation for removing the surface layer of concrete 29, for example the surface layer of a reinforced concrete roadbed of a bridge, where the water jet breaks away the deteriorated surface layer that is to be renewed. The reinforcement has been denoted 30. The tube 22 is shown during the movement of the carriage 20 to the right in the figure with the tube having an attack angle to the concrete surface.

[0007] When the working has reached the right end line, the hydraulic cylinder 26, figure 2, swings the tube 22 into a corresponding attack angle for a working sweep to the left in the figure. In this turning point the entire vehicle is stepped forwards some centimetres by means of the motors 12 in figure 1. The operation sequence is suitable the one described in WO-0231265 and it is not described in detail but reference is made to the publication. The entire operation sequence is computer controlled and the various parameters such as attack angle, the velocity and end positions of the carnage, the step length, etc. are controlled from the operator's consol 39 in figure 1.

[0008] Figure 4 illustrates an electronic control unit 40, controlled from the operator's console 39, and a wire diagram for controlling the hydraulic motors 12,21,24,26 mentioned above. Each hydraulic motor is coupled to its electrically controlled distribution valve 41-44 by hydraulic conduits (hoses) 45,46; 47,48; 49,50; 51,52. The supply and drain conduits of the distribution valves are not illustrated. One of the hydraulic conduits of each motor has a flow meter in the form of a pulse transducer 55-58 coupled to the control unit. Each pulse transducer meters the flow through it and gives for every pre-determined volume unit that passes an electric pulse to the respective control unit via the respective electric line 60-63. The pre-determined volume units can for example be in the order of 0.2 cm³ which will provide sufficient accuracy. The entire system with control unit, distribution valves, and pulse transducers can be placed well protected in the vehicle 11, that is, well protected at a distance from the feed beam 15, and only the hydraulic conduits 47-52 of the hydraulic motors lead from the vehicle via the foldable arm 13,14 to the hydraulic motors 21,24,26 on the carriage 20. In accordance with the invention, at least one of the hydraulic motors 21,24,26 or preferably all three of them can be controlled in this way and their meters (pulse transmitters) will not be in the hazardous environment on the feed beam. The hydraulic motors 12 ( only one of them is illustrated in the diagram) for the advancement of the vehicle can suitably be controlled in the same way as illustrated.

[0009] In the illustrated example of the invention, the working unit, that is, the feed beam 15 and the carriage 20, is carried by the foldable and extensible arm 13,14 that is mounted on the vehicle 11. The arm and the vehicle is thus a carrier for the working unit. The carrying unit of the vehicle, that is, the arm 13,14, can alternatively be separated from the vehicle/power unit 11 and be a separately carried long arm in order to make possible the working of other surfaces than a roadbed, for example the foundation of a bridge and also the parts of the foundation that are under water. The stepping between the working sweeps can then be carried out by the foldable and extensible arm. The operation of the working unit 15,20 is extremely reliable since it has no active electric sensors or meters nor any electric lines, and it can therefore be used under water. Reference sensors can be used for control and calibration, but any malfunction of them or their electric lines does not disturb the working operation and does not reduce the reliability.

[0010] The carrying unit for the working unit can alternatively be a stiff guide or two guiding wire ropes that extend down along a foundation in the water while the vehicle 11 is on the roadbed and coupled to the working unit 15,20 only by long hydraulic hoses. The stepping between the working sweeps will then be carried out by a stepping motor on the feed beam that moves the feed beam along the guide or guiding wire ropes.

Claims

1. A concrete working machine for working a concrete surface, comprising: a carrier (11,13,14), with a transverse feed beam (15) that carries a carriage (20) with a water jet nozzle (22,23), a first hydraulic motor (21) for moving the carriage along the feed beam, a second hydraulic motor (26) for pivoting the nozzle about a first axis (I) so as to give it an attack angle to the concrete in both directions when the carriage is reciprocated in working sweeps, and a third hydraulic motor (24) for pivoting the nozzle about a second axis (II) for oscillating it in a plane transverse to the feed beam,
characterised by
flow meters (56-58) in the hydraulic lines (47-52) of at least some of the hydraulic motors (21,24,26), coupled to an electronic control unit (40) for distribution valves (42-44) in the hydraulic conduits, the flow meters being positioned at a distance from the feed beam (15).

2. A concrete working machine according to claim 1, characterised in that the flow meters are pulse transducers (56-58).

3. A concrete working machine according to claim 1 or 2, characterised in that the carrier (11,13,14) comprises a mobile unit (11) with an arm (13,14) on the end of which the feed beam (15) is mounted, and a hydraulic motor(12) for stepping the mobile unit is also controlled by a flow meter (55) in one of the hydraulic lines (45) of the motor (12).

Ansprüche

1. Betonbearbeitungsmaschine zur Bearbeitung einer Betonoberfläche, mit: einem Träger (11, 13, 14) mit einem Vorschub-Querbalken (15), der einen Laufwagen (20) mit einer Wasserstrahldüse (22, 23) trägt, einem ersten Hydromotor (21), um den Laufwagen entlang dem Vorschubbalken zu bewegen, einem zweiten Hydromotor (26) zum Drehen der Düse um eine erste Achse (I), um ihr einen Angriffswinkel zu dem Beton in beiden Richtungen zu verleihen, wenn der Laufwagen in Arbeitsdurchläufen hin- und herbewegt wird, und einem dritten Hydromotor (24) zum Drehen der Düse um eine zweite Achse (II), um sie in einer Ebene quer zum Vorschubbalken hin- und herzubewegen, gekennzeichnet durch Strömungsmesser (56 - 58) in den Hydraulikleitungen (47 - 52) mindestens einiger der Hydromotoren (21, 24, 26), verbunden mit einer elektronischen Steuerungseinheit (40) für Verteilerventile (42 - 44) in den hydraulischen Leitungen, wobei die Strömungsmesser von dem Vorschubbalken (15) beabstandet sind.

2. Betonbearbeitungsmaschine nach Anspruch 1, gekennzeichnet dadurch, dass die Strömungsmesser Impulswandler (56 - 58) sind.

3. Betonbearbeitungsmaschine nach Anspruch 1 oder 2, gekennzeichnet dadurch, dass der Träger (11, 13, 14) eine bewegliche Einheit (11) mit einem Arm (13, 14) umfasst, an dessen Ende der Vorschubbalken (15) montiert ist, und dass ein Hydromotor (12) zum Schalten der beweglichen Einheit auch von einem Strömungsmesser (55) in einer der Hydraulikleitungen (45) des Motors (12) kontrolliert wird.

Revendications

1. Machine à travailler le béton pour travailler une surface de béton, comprenant : un transporteur (11, 13, 14) avec une poutre d'alimentation transversale (15) qui porte un chariot (20) avec un gicleur à jet d'eau (22, 23), un premier moteur hydraulique (21) pour déplacer le chariot le long de la poutre d'alimentation, un deuxième moteur hydraulique (26) pour faire pivoter le gicleur autour d'un premier axe (I), de façon à lui donner un angle d'attaque au béton dans les deux directions quand les déplacements du chariot décrivent un mouvement avant - arrière, et un troisième moteur hydraulique (24) pour faire pivoter le gicleur autour d'un deuxième axe (II) pour le faire osciller dans un plan transversal par rapport au à la poutre d'alimentation,
caractérisée par
des débitmètres (56 - 58) dans les lignes hydrauliques (47 - 52) d'au moins quelques-uns parmi les moteurs hydrauliques (21, 24, 26), accouplés à une unité de commande électronique (40) pour des soupapes de distribution (42 - 44) dans les conduits hydrauliques, les débitmètres étant positionnés à une distance du faisceau d'alimentation (15).

2. Machine à travailler le béton selon la revendication 1, caractérisée en ce que les débitmètres sont des transducteurs d'impulsions (56 - 58).

3. Machine à travailler le béton selon la revendication 1 ou 2, caractérisée en ce que le support (11, 13, 14) comprend une unité mobile (11) avec un bras (13, 14) à l'extrémité duquel la poutre d'alimentation (15) est montée, et un moteur hydraulique (12) pour commuter l'unité mobile est également contrôlé par un débitmètre (55) dans une des lignes hydrauliques (45) du moteur (12).

Drawing