Large manipulator having an articulated mast that can be quickly folded and unfolded

Abstract

A large manipulator includes a chassis, a turntable arranged on the chassis and rotatable around a vertical axis via a rotary drive, and an articulated mast including two or more mast segments pivotably-movably connected, via articulated joints, with the respectively adjacent turntable or mast segment via a respective drive. The large manipulator further includes a mast sensor system configured to detect position of at least one point of the articulated mast or a pivot angle of at least one articulated joint and configured to generate sensor output signals. The large manipulator further includes a control device configured to actuate the drive in a normal operation for mast movement and to limit speed of movement of the articulated mast depending upon the sensor output signals. The drive is manually controllable in an emergency operation. The large manipulator further includes at least one limiting means, which, in the emergency operation, limit speed of the drive to a pre-specified maximum value.

Claims

1. A large manipulator comprising: a chassis; a turntable arranged on the chassis and rotatable around a vertical axis via a rotary drive; an articulated mast including two or more mast segments pivotably-movably connected, via articulated joints, with the respectively adjacent turntable or mast segment via a respective drive; a mast sensor system configured to detect position of at least one point of the articulated mast or a pivot angle of at least one of the articulated joints and configured to generate sensor output signals; a control device configured to actuate the drive in a normal operation for mast movement and to limit the speed of movement of the articulated mast depending upon the sensor output signals, wherein the drive is manually controllable in an emergency operation; and at least one limiting means, which, in the emergency operation, limits speed of the drive to a pre-specified maximum value.

2. The large manipulator according to claim 1, wherein a control valve is connected to hydraulic working lines of the drive for the actuation thereof, wherein the control valve, in the normal operation, is actuated via the control device, which limits adjusting of the mast segment such that a pre-specified traversing speed is not exceeded.

3. The large manipulator according to claim 1, wherein the control valve is a proportional valve and has a travel path, wherein the at least one limiting means limits the travel path.

4. The large manipulator according to claim 1, wherein the at least one limiting means mechanically limits a travel path of the control valve.

5. The large manipulator according to claim 4, wherein the at least one limiting means includes a hand lever adjustable in the emergency operation, wherein the hand lever is adjustable between two stops, which mechanically limit adjustment.

6. The large manipulator according to claim 1, wherein the at least one limiting means electronically limits a travel path of the control lever.

7. The large manipulator according to claim 6, wherein the at least one limiting means includes an electric emergency control used in the emergency operation, wherein the emergency control provides an electrical voltage for actuating the control valve that is reduced compared to the electrical voltage provided by the control device in the normal operation.

8. The large manipulator according to claim 7, wherein the reduced voltage of the emergency control shortens the travel path.

9. The large manipulator according to claim 1, wherein the at least one limiting means includes an emergency valve connected in parallel to the control valve.

10. The large manipulator according to claim 9, wherein the emergency valve comprises activatable hand levers.

11. The large manipulator according to claim 9, wherein the emergency valve limits flow rate of the control device.

12. The large manipulator according to claim 1, further comprising a quick-traverse valve, connected in parallel to the control valve and/or an emergency valve for fast adjustment of the mast segment.

13. The large manipulator according to claim 1, wherein the at least one limiting means provides a centralized limitation of hydraulic pressure made available by a hydraulic pump at hydraulic working lines of the control valve.

14. The large manipulator according to claim 1, wherein the at least one limiting means provides a centralized limitation of hydraulic fluid volume made available by a hydraulic pump at hydraulic working lines of the control valve.

15. The large manipulator according to claim 1, wherein the at least one limiting means is configured as a pressure balance, which, in the emergency operation, is set such that it reduces hydraulic pressure made available by a hydraulic pump on hydraulic working lines of the control valve with respect to set hydraulic pressure in the normal operation.

Description

(1) Further features, details and advantages of the invention result due to the following description, as well as based on the illustrations. Exemplary embodiments of the invention are shown purely schematically in the following illustrations, and are further described in the following. Mutually corresponding subject-matters or elements are provided with the same reference characters throughout the figures. Shown are in:

(2) FIG. 1: a large manipulator according to the invention with an articulated mast in a configuration,

(3) FIG. 2a: a control valve,

(4) FIG. 2b: a control valve with a hand lever,

(5) FIG. 3: a control valve with electric emergency controller,

(6) The representation according to FIG. 1 schematically shows a large manipulator 1 configured as a truck-mounted concrete pump, with a chassis 2, on which a turntable 3 is arranged which, by means of a hydraulic rotary drive 6, is rotatable around an upright axis 16 of the large manipulator 1. An articulated mast 4, denoted in totality with the reference character 4, is hinged on the turntable 3, which mast, in the illustrated exemplary embodiment, includes four mast segments 5a, 5b, 5c, and 5d. The first mast segment 5a is arranged pivotally movably around a horizontal axis on the turntable 3, via a joint. The pivotal movement is effected through a pivot drive 6a. The remaining mast segments 5b, 5c and 5d are pivotally movably connected, via articulated joints, around horizontal axes parallel to one another, with the respectively connected mast segments 5a, 5b, 5c, 5d. The pivotal movement likewise respectively effects a pivot drive 6a, 6b, 6c, 6d. The pivot drives 6a, 6b, 6c, 6d each comprise one (or multiple) hydraulic cylinders, which are actuated via proportionally working control valves 8 (FIG. 2a, 2b, 3). These, in turn, are controlled by an electronic control device 7 (FIG. 3) for the mast movement.

(7) The large manipulator 1 according to the invention comprises a mast sensor system (e.g. in the form angle sensor for the joints, path sensors for the detection of the piston positions of the individual hydraulic cylinders or geodetic inclination sensors). With the aid of the mast sensor system, the pivot angles φ.sub.1, φ.sub.2, φ.sub.3 and φ.sub.4, of the articulated joints, are detected, for example, wherein the control device 7 (FIG. 3), in the normal operation, controls, through corresponding actuation of the control valves 8 (FIG. 2a, 2b, 3) of the hydraulic cylinders, the speed of the mast movement, dependent upon the momentary pivot angles φ.sub.1, φ.sub.2, φ.sub.3 and φ.sub.4 of the articulated joints. A control device 7 (FIG. 3) actuating the drives 6, 6a, 6b, 6c, 6d in a normal operation is set up to control the mast movement of the articulated mast 4. To that end, the position of at least one point of the articulated mast 4 or a pivot angle φ1, φ2, φ3, φ4 of at least one articulated joint is detected, in the normal operation, via the mast sensor system. In the normal operation, the speed of the mast movement is limited through the control device 7 (FIG. 3), depending upon the momentary output signals of the mast sensor system. This takes place in particular in that the traversing speed of at least one of the drives 6, 6a, 6b, 6c, 6d is limited to a variable maximum value dependent upon the momentary output signals of the mast sensor system. In the emergency operation, such as in a malfunction of the mast sensor system or other electronic components, the drives 6, 6a, 6b, 6c, 6d are manually controllable. At least one limiting means 11, 12, 13, 14 (FIG. 2a, 2b, 3) is provided for the emergency operation, which means limits the traversing speed of at least one of the drives 6, 6a, 6b, 6c, 6d to a fixedly pre-specified maximum value.

(8) This maximum value, fixedly pre-specified for the individual drives 6, 6a, 6b, 6c, 6d, is configured such that, even in a simultaneous traversing of all drives 6, 6a, 6b, 6c, 6d, the maximally permitted speed of the mast movement cannot be exceeded. If, in the emergency operation, the simultaneous operation of multiple drives 6, 6a, 6b, 6c, 6d is not possible, the limiting means can be designed such that, in the traversing of the selected drive 6, 6a, 6b, 6c, 6d, the permitted speed of the mast movement is not exceeded.

(9) FIG. 2a schematically shows a control valve 8, which is connected with the hydraulic working lines 9b, 10b to actuate a drive 6, 6a, 6b, 6c, 6d (FIG. 1). Each of the drives 6, 6a, 6b, 6c, 6d (FIG. 1) is assigned a distinct control valve 8. Via hydraulic working lines 9a, 10a, the control valve 8 is connected with a hydraulic pump (not illustrated) which provides the hydraulic pressure or the necessary hydraulic fluid volumes necessary for the traversing of the articulated mast. The drive 6, 6a, 6b, 6c, 6d (FIG. 1) is supplied with hydraulic pressure via the hydraulic working lines 9b, 10b by the control valve 8, so that the drive 6a, 6b, 6c, 6d (FIG. 1) pivots the mast segments 5a, 5b, 5c, 5d (FIG. 1) against one another via the articulated joint or the drive 6 causes a pivotal movement of the articulated mast 4. The control valve 8 is actuated, in the normal operation, via the control device 7 (FIG. 3), in order to effect the mast movement of the articulated mast 4 via the actuation of the valve piston 18 by means of the valve piston control device 18a. The electronic actuation of the control valve 8 can, as shown in FIG. 3, occur via a variable voltage signal, but also, for example, via an electronic digital signal. The control device 7 (FIG. 3) limits the movement of the mast segment 5a, 5b, 5c, 5d (FIG. 1), in the articulated joint or in the turntable 3 in such a manner that the speed of the mast movement is limited depending upon the momentary output signals of the mast sensor system. This occurs in particular in that the traversing speed of the drive 6, 6a, 6b, 6c, 6d (FIG. 1) is limited to a variable maximum value, dependent upon the momentary output signals of the mast sensor system. In this way, the control device 7 (FIG. 3) can limit the speed of the mast movement, so that a pre-specified mast speed is not exceeded.

(10) The valve piston 18 of the control valve 8, embodied as proportional valve, according to FIG. 2a, comprises an travel path S indicated by two vertical arrows. In order to limit the traversing speed of the drive 6, 6a, 6b, 6c, 6d (FIG. 1) to a fixedly pre-determined maximum value, in the emergency operation, a mechanical limiting of the adjustment path S is provided. This mechanical limiting is represented in FIG. 2b. In the emergency operation, a hand lever 11 is fitted onto the socket 17. This hand lever 11 is then displaceable between the two stops 12, 13, in the emergency operation, wherein the stops 12, 13 mechanically limit the displacement. This is indicated in FIG. 2b through the hand levers 11 indicates in dashed line, in the two stopping positions. Through the displacement of the hand lever 11, the drive 6, 6a, 6b, 6c, 6d (FIG. 1) is manually controllable, in the emergency operation, via the control valve 8. As is to be can be taken from FIG. 2a, the non-fitted hand lever does not contact the stops 12, 13 in the normal operation, so that the travel path S of the control valve 8 is not mechanically limited here. The displacement, at the control valve 8, is thusly possible, in the normal operation, via the full piston travel. An unimpaired actuation of the valve piston 18 of the control valve 8 hereby occurs, via the electronic or hydraulic valve piston activation device 18a, through the control device 7 (FIG. 3) to adjust the mast segment 5a, 5b, 5c, 5d (FIG. 1) in the normal operation. In the normal operation, the socket 17 is pivotable by about 80 degrees, which is indicated through the dashed outlines, while the limiting, in the emergency operation, permits a pivot angle of the hand lever 11 of around 40 degrees through the stops 12, 13 on the slotted link. In the emergency operation, the electronic or hydraulic valve piston activation device 18a is out of service. In the emergency operation, only one control valve 8 for the drives 6, 6a, 6b, 6c, 6d, for example, ca be actuated with a single hand lever, so that a simultaneous traversing of multiple drives 6, 6a, 6b, 6c is not possible. In this case, the limiting is designed such that the maximum permitted mast movement speed is not possible in the actuation of a drive 6, 6a, 6b, 6c, 6d .

(11) The shown control valve 8 can be a 4/3-way proportional valve, with which the hydraulic cylinder is directly actuated. The control valve 8 can also be configured as a pilot valve or relay valve for the actuation of the 4/3-way proportional valve.

(12) FIG. 3 shows a control valve 8 configured as a proportional valve. The travel path S of the valve piston 18 is indicated by the two vertical arrows. The adjustment of the valve piston 18 on the travel path S occurs via the electrical valve piston activation device 18a. The valve piston activation device 18a is actuated via the control device 7, in the normal operation, which device receives travel commands from the user of the large manipulator 1 (FIG. 1) by means of the remote control 20 and the receiver 21. In the emergency operation, a means for electronic limiting of the travel path S is provided. The traversing speed of the drive 6, 6a, 6b, 6c, 6d (FIG. 1) can hereby be limited to a fixedly pre-specified maximum value. In the shown exemplary embodiment, the electronic limiting is provided through an emergency controller 14 used in the emergency operation. The emergency controller 14 makes an electrical voltage for actuating the valve piston activation device 18a available, reduced relative to the voltage made available through the control device 7 in the normal operation. Through the reduced voltage of the emergency controller 14, the travel path S of the control valve is limited in the emergency operation, so that the traversing speed of the drive 6, 6a, 6b, 6c, 6d is limited to a fixedly pre-specified maximum value. In the normal operation, the control device 7 makes a voltage between −9 V and +9 V available for actuating the control valve 8, so that the valve piston 18 can be displaced through the valve piston activation device 18a over the full piston path. A changeover switch 19 is provided for switching over between normal operation and emergency operation. The actuation of this changeover switch 19 leads to the articulated mast 4 (FIG. 1) being able to be displaced, in the emergency operation, via the electric emergency controller. The emergency controller 14, to that end, makes available a fixedly set reduced voltage of, for example, +4 V and −4 V, for actuating the control valve 8 via the valve piston activation device 18a, whereby the travel path of the control valve 8 is correspondingly shortened. The voltage of the emergency controller for actuating the control valves 8 can, however, also be regulated from −4 V to +4 V. In this way, it can be ensured that the traversing speed of the drive 6, 6a, 6b, 6c, 6d (FIG. 1) is limited to a fixedly pre-specified maximum value in the emergency operation. The shown control valve 8 can relate to a 4/3-way proportional valve, with which the hydraulic cylinder is directly actuated. The control valve 8 can, however, also be configured as a pilot valve or relay valve for actuating a 4/3-way proportional valve.

(13) If multiple control valves 8 or drives 6, 6a, 6b, 6c, 6d can be simultaneously controlled via the emergency controller 14, the limiting can, for example, be configured such that, in a simultaneous traversing movement of multiple of the drives 6, 6a, 6b, 6c, 6d, the maximum permitted speed of the mast movement is not exceeded.

(14) The following is a detailed explanation of an exemplary embodiment of an algorithm for mast controlling, in the normal operation, based on an articulated mast of a large manipulator, which comprises an arbitrary number of N joints, and is anchored to a fixed point on the chassis 2 with a turntable 3. FIG. 1 representatively shows the case of a truck-mounted concrete pump 1 with an articulated mast 4 comprising N=4 joints. The elastic deformation of the individual mast segments 5a, 5b, 5c, 5d is neglected, so that these are considered as rigid bodies. The description of the kinematics of the system is required for establishing the speed of the end point EP of the articulated mast 4, which corresponds to the mast tip 15 in the following. The rigid body angles φ.sub.i for i=1, . . . , N, as well as the rotation angle θ of the turntable 3, around the vertical rotary axis thereof, are the degree of freedom of the system. The absolute movements of the system are described in the inertial coordinate system 0.sub.0x.sub.0y.sub.0z.sub.0, i.e. in the coordination system that is fixed with respect to the chassis 2. With 0.sub.dx.sub.dy.sub.dz.sub.d, that coordinate system is denoted, which is rotated relative to the inertial coordinate system by the rotation angle θ. Moreover, a local coordinate system 0.sub.ix.sub.iy.sub.iz.sub.i is defined for each mast segment 5a, 5b, 5c, 5d, the x.sub.i axis of which system extends along the longitudinal axis of the respective mast segment 5a, 5b, 5c, 5d. As the mast segments typically have a bend, for i≥2, at the beginning, the longitudinal axis thereof does not intersect the respective joint axis. The origin of each local coordinate system is therefore set at the point of intersection of the longitudinal axis with that orthogonal straight line which extends through the joint axis. The spaces between the joint axes and the origins of the local coordinate systems are denoted with D.sub.i for i=2, . . . , N.

(15) The kinematic relationships between the local coordinate systems and the inertial coordinate system can be represented with rotation matrixes and translation vectors. The inertial coordinates of a point on the longitudinal axis of the i-th mast segment r.sub.1.sup.i(x.sub.i)=[x.sub.i, 0, 0].sup.T, described in the local coordinate system i (characterized by the index below), are specified through
r.sub.0.sup.i(x.sub.i)=R.sub.0.sup.ir.sub.i.sup.i(x.sub.i)+d.sub.0.sup.i

(16) The matrix
R.sub.0.sup.i=R.sub.0.sup.dR.sub.d.sup.1R.sub.1.sup.2 . . . R.sub.i-1.sup.i

(17) with

(18) $R_0^d=\left[\begin{array}{ccc}\cos \left(\theta \right)& 0& -\sin \left(\theta \right)\\ 0& 1& 0\\ \sin \left(\theta \right)& 0& \cos \left(\theta \right)\end{array}\right]$$R_d^1=\left[\begin{array}{ccc}\cos \left({\phi }_1\right)& -\sin \left({\phi }_1\right)& 0\\ \sin \left({\phi }_1\right)& \cos \left({\phi }_1\right)& 0\\ 0& 0& 1\end{array}\right]$$\mathrm{and}$$R_{j-1}^j=\left[\begin{array}{ccc}\cos \left({\phi }_j\right)& -\sin \left({\phi }_j\right)& 0\\ \sin \left({\phi }_j\right)& \cos \left({\phi }_j\right)& 0\\ 0& 0& 1\end{array}\right]$

(19) for j=2, . . . , N describes the rotation of the local coordinate system 0.sub.ix.sub.iy.sub.iz.sub.i relative to the inertial coordinate system 0.sub.0x.sub.0y.sub.0z.sub.0. The translational displacement d.sup.i.sub.0 between the local coordinate system 0.sub.ix.sub.iy.sub.iz.sub.i and the inertial coordinate system 0.sub.0x.sub.0y.sub.0z.sub.0 is specified through
d.sub.0.sup.j=R.sub.0.sup.j-1 d.sub.j-1.sup.j+d.sub.0.sup.j-1

(20) for j=2, . . . . , N with d.sup.i.sub.0=[0, 0, 0].sup.T, and

(21) $d_{j-1}^j=R_{j-1}^j\left[\begin{array}{c}0\\ D_j\\ 0\end{array}\right]+\left[\begin{array}{c}{L}_{j-1}\\ 0\\ 0\end{array}\right]$

(22) Here, L.sub.j refers to the length of the j-th mast segment.

(23) The inertial coordinates of the end point EP of the N-th mast segment can thusly be represented as a function of the positions of the N joints and of the und turntable 3 through r.sub.0,N.sup.EP (q)=r.sub.0.sup.N(L.sub.N) with the vector of the degrees of freedom q=[θ, φ.sub.1, . . . , φ.sub.N].sup.T. The speed of the end point EP in the direction of the individual coordinate axes results through differentiation after the time at

(24) ${\stackrel{.}{r}}_{0,N}^{\mathrm{EP}}\left(q\right)=\frac{\partial r_{0,N}^{\mathrm{EP}}\left(q\right)}{\partial q}\stackrel{.}{q}=J_{q,N}^{\mathrm{EP}}\stackrel{.}{q}.$

(25) Through the employed hydraulic systems, in combination with the control device, a proportional control of the traversing speeds of the individual hydraulic cylinders 6a, 6b, 6c, 6d and of the rotary drive 5 is made possible for the operator of the large manipulator according to the invention. The resulting joint angle speeds can be determined by knowledge of the translation of the joint kinematics, based on the target speeds for the hydraulic cylinders 6a, 6b, 6c, 6d. The piston position s.sub.z,i of a cylinder 6a, 6b, 6c, 6d, can generally be represented as a non-linear function of the corresponding joint angle φ.sub.i,
s.sub.z,i=f.sub.x,i(φ.sub.i).

(26) At the speed level, the correlation

(27) ${\stackrel{.}{s}}_{z,i}=\frac{\partial f_{z,i}\left({\phi }_i\right)}{\partial {\phi }_i}{\stackrel{.}{\phi }}_i$

(28) applies, where, from a pre-specified piston speed ŝ.sub.z,i.sup.d, the resulting joint angle speed can be established. Moreover, with this correlation, the corresponding piston speed can be calculated, reversed, from a pre-specified joint angle speed. Thusly, a uniform, proportional control of the joint angle speeds is made possible for the user. This is of particular advantage for the user, as the generally non-avoidable non-linearity of the joint kinematics is thereby compensated. The vector
{dot over (q)}=[{dot over (θ)}.sup.d, {dot over (φ)}.sub.1.sup.d, . . . , {dot over (φ)}.sub.N.sup.d].sup.T

(29) is therefore representative for the user inputs, i.e. the travel command in the context of the invention, which specifies the target speeds of the drives, or directly of the joints. The use of a suitable mast sensor system is necessary for the detection of the joint positions or of the degree of freedom q.

(30) The absolute speed of the boom tip EP is specified by

(31) $v^{\mathrm{EP}}=\sqrt{{{\stackrel{.}{q}}^T\left(J_{q,N}^{\mathrm{EP}}\right)}^T{J}_{q,N}^{\mathrm{EP}}\stackrel{.}{q}}.$

(32) If said absolute speed exceeds the maximum permitted speed v.sup.EP.sub.max, all speeds of the drives 6, 6a, 6b, 6c, 6d will be uniformly, i.e. by the same factor, reduced, through the control device, relative to the target speeds pre-specified through the travel command. A vector {dot over (q)}.sub.red is thusly sought, for which

(33) $v_{\max }^{\mathrm{EP}}=\sqrt{{{\stackrel{.}{q}}_{\mathrm{red}}^T\left(J_{q,N}^{\mathrm{EP}}\right)}^T{J}_{q,N}^{\mathrm{EP}}{\stackrel{.}{q}}_{\mathrm{red}}}$

(34) applies. Through the requirement for the simultaneous reduction of the speeds, this problem permits itself to be clearly solved and simplified, to the determination of a factor k.sub.red ∈R, with {dot over (q)}.sub.red=k.sub.red{dot over (q)}. Thusly

(35) $v_{\max }^{\mathrm{EP}}=\sqrt{k_{\mathrm{red}}^2{{\stackrel{.}{q}}^T\left(J_{q,N}^{\mathrm{EP}}\right)}^T{J}_{q,N}^{\mathrm{EP}}\stackrel{.}{q}}$

(36) applies, where from the correlation

(37) $k_{\mathrm{red}}=\frac{v_{\max }^{\mathrm{EP}}}{\sqrt{{{\stackrel{.}{q}}^T\left(J_{q,N}^{\mathrm{EP}}\right)}^T{J}_{q,N}^{\mathrm{EP}}\stackrel{.}{q}}}$

(38) follows. The result for the modified travel command {dot over (q)}.sub.red, i.e. with speeds reduced relative to the user-sided specification {dot over (q)} is finally

(39) ${\stackrel{.}{q}}_{\mathrm{red}}=\frac{v_{\max }^{\mathrm{EP}}}{\sqrt{{{\stackrel{.}{q}}^T\left(J_{q,N}^{\mathrm{EP}}\right)}^T{J}_{q,N}^{\mathrm{EP}}\stackrel{.}{q}}}\stackrel{.}{q}.$

(40) The control device actuates the rotary drive 6 and the hydraulic cylinder 6a, 6b, 6c, 6d in accordance with this modified travel command, and limits the movement speed thereof, so that the mast tip EP never moves faster than legally permitted. Simultaneously, the traversing speed can be maximally fast within the legal framework, in any desired mast position, whereby considerable time can be saved in the unfolding and folding of the articulated mast 4, but also in the displacement of the mast between to working positions, relative to the prior art.

(41) The invention, in brief summary, relates to a large manipulator 1, in particular a truck-mounted concrete pump, with a turntable 3 rotatable around a vertical axis by means of a rotary drive, which table is arranged on a chassis 2, an articulated mast 4, which includes two or more mast segments 5a, 5b, 5c, 5d, wherein the mast segments 5a, 5b, 5c, 5d are pivotally movably connected, via articulated joints, with the respectively adjacent turntable 3 or mast segment 5a, 5b, 5c, 5d, by means of in each case one drive (6, 6a, 6b, 6c, 6d), with a control device 7 actuating the drives 6, 6a, 6b, 6c, 6d in a normal operation for the mast movement, and a mast sensor system for detecting the condition of at least one point of the articulated mast (4), or of a pivot angle φ1, φ2, φ3, φ4 of at least one articulated joint. It is the object of the invention to be able to bring the articulated mast from the completely folded state into its desired working position in minimal time. Likewise, it is to be ensured, also in case of a failure of the mast sensor system, that the traversing speed of the drives complies with legal standards. To that end, the invention proposes that the control device 7 is configured to limit the speed of the mast movement in that the mast speed is limited to a maximum value depending on the momentary output signals of the mast sensor system, wherein the drives 6, 6a, 6b, 6c, 6d can be manually controlled in emergency operation, wherein at least one limiting means 11, 12, 13, 14 is provided, which, in emergency operation, limits the traversing speed of at least one of the drives 6, 6a, 6b, 6c, 6d to a fixedly specified maximum value. The invention also relates to a method for controlling the movement of an articulated mast of a large manipulator. list of reference characters

LIST OF REFERENCE CHARACTERS

(42) 1 large manipulator

(43) 2 chassis

(44) 3 turntable

(45) 4 articulated mast

(46) 5 5a, 5b, 5c, 5d mast segment

(47) 6 6a, 6b, 6c, 6d drive

(48) 7 control device

(49) 8 control valve

(50) 9 9a, 9b hydraulic working line

(51) 10 10a, 10b hydraulic working line

(52) 11 hand lever

(53) 12 stop

(54) 13 stop

(55) 14 electric emergency controller

(56) 15 mast tip

(57) 16 upright axis

(58) 17 socket of hand lever

(59) 18 valve piston 18a valve piston actuation device

(60) 19 changeover switch

(61) 20 remote control

(62) 21 receiver