FR2620590A1 - Machine for cutting trees into a curtain - Google Patents

Abstract

Machine for cutting trees into a curtain, preferably built in the form of a self-propelled platform, characterised in that it comprises an elevator 1 the upper part 10 of which is equipped with an orientable guide chassis 12 carrying a movable carriage 26 provided with an extensible and orientable articulated arm 35, on the pivoting end part 39 of which is fixed a cutting head 57; the latter including a tool-carrying balance arm 48 fixed, with a capability of reciprocating pivoting, onto the pivoting end portion 39 of the articulated arm 36-39, and provided with at least one cutting member 53, 53'.

Description

Machine for pruning curtain trees.

 The present invention relates to a machine for pruning curtain trees which, according to a preferred but not exclusive embodiment, is produced in the form of a self-propelled platform.

 This machine is more particularly intended to allow the "curtain" pruning of trees bordering the paths allocated to automobile, pedestrian or other traffic, such as streets, avenues, alleys, etc., in particular in built-up areas, and along which may find obstacles such as parked vehicles.

 Currently, this work is carried out manually by pruners who use - on the one hand, a double pruning ladder fixed on a trolley fitted with wheels; the pruner parked on a board placed on the penultimate bar of the uprights of said ladder, with its legs placed on either side of the top of the latter; - on the other hand, a tool consisting of a cutting crescent mounted at one end of a handle with a length of 6 to 8 m and made of chestnut wood.

 The pruner makes the side cut using this tool, hitting the branches with flail movements, then he operates the horizontal cut by similar movements made flat on the top of the tree. The carriage is then pushed along the line of trees in order to be able to carry out a new cutting action.

 We understand that this is tiring work, requiring a robust constitution, unusual qualities of resistance and great skill. This work can therefore only be carried out by very specialized and experienced performers whose training requires a lot of time.

 In addition, the quality of the cut can vary depending on the skill of the pruner or his degree of fatigue.

 In addition, this way of proceeding presents certain risks of accident, in particular due to the instability of the lift assembly, the branches to be cut being at a height often exceeding 10 m.

 Finally, the daily assembly and disassembly of the lift assembly which cannot be left parked at the place of use during periods of inactivity, cause costly time losses.

 The object of the invention is in particular to remedy the aforementioned drawbacks.

 According to the invention, this objective is achieved by means of a machine, preferably produced in the form of a self-propelled platform and comprising: an elevator, the upper part of which is equipped with a guide frame carrying a mobile carriage provided with a articulated arm on the pivoting end part of which is fixed, with a pivoting ability, a tool-carrying pendulum provided with at least one cutting member.

 The machine according to the invention makes it possible to mechanically prune the curtain trees, without the operators having to carry out strenuous physical efforts.

It can be carried out by operators whose training requires little time.

 The quality of the cut performed using this machine is perfect, the pruning can be carried out without problem when dry in winter) or green on foliage (in summer).

 The machine, executed in the form of a self-propelled size platform, is designed to move easily from one site to another; it is fully autonomous, two operators sufficient for the management of a large site.

 This size self-propelled platform can be compared to mobile scaffolding, working in a fixed position. It offers all the desirable security guarantees.

The aims, characteristics and advantages above, and others still, will emerge more clearly from the following description and from the appended drawings in which
Figure 1 is a side view of a size self-propelled platform according to the invention, the elevator of which is shown in the folded position according to which said self-propelled platform fits in a template conforming to the highway code and allowing its circulation on the entire road network.

 Figure 2 is a simplified plan view of this size self-propelled platform.

 Figure 3 is another side view of the size self-propelled platform whose elevator is illustrated in a deployed working position.

 Figure 4 is a front view of the size self-propelled platform shown in a similar position, during the pruning of the top of a tree; the lines drawn in fine lines show some possible positions of the cutting head, the line drawn in mixed lines illustrating the pivoting of the tool-carrying balance.

 Figure 5 is a partial front view illustrating the mounting of stops fitted to the elevator, in order to avoid its complete "compaction", when it is in the low position.

 FIG. 6 is a side view of FIG. 5.

 Figure 7 is a schematic cross-sectional view of the upper part of the machine, the movable arm is -oriented in the working position.

 Figure 8 is a simplified plan view showing the means ensuring the orientation of the guide frame relative to the upper frame of the elevator.

 Figure 9 is a cross-sectional view along line 9-9 of Figure 8.

 Figure 10 is a detail view, in section along line 10-10 of Figure 9 and showing one of the means contributing to the stable mounting of the guide frame on the upper frame of the elevator.

Figure It is a plan view with partial section, of the mobile carriage of the machine.
Figure 12 is a detail view showing the carriage drive system.

 FIG. 13 is a front view of the extendable and articulated arm of the machine shown in the working position and the sliding element of which is shown in the retracted position.

 Figure 14 is a plan view of Figure 13.

 FIG. 15 is a fragmentary front view, with partial section, of the orientable arm and, more precisely, of the means allowing the movements of its articulated end.

 Figure 16 is a detail view illustrating the drive means of the tool holder balance.

 Figure 17 is a plan view of Figure 16.

 Figure 18 is a front view of an exemplary embodiment of the cutting head of the machine.

 Figure 19 is a plan view of Figure 18.

Figures 20 and 21 are schematic views illustrating an example of pruning of curtain trees carried out using a self-propelled platform of size according to
The invention.

 Reference is made to said drawings to describe an example of an interesting, but in no way limiting, embodiment of the machine for pruning curtain trees according to the invention.

 According to this example, the pruning machine is produced in the form of a self-propelled platform, but the invention does not exclude the possibility of executing it in the form of a pruning platform intended to be towed by a tractor vehicle.

 This machine comprises an elevator 1 advantageously constituted by a crossover elevator known per se.

 This elevator comprises a lower frame 2 constituted by an assembly of robust metal beams and rigidly fixed on the chassis 3 of an automobile truck 4.

Each angle of this frame is fitted with a retractable stabilizing foot 5 allowing the self-propelled platform to be immobilized on the ground, in the working position. The machine is equipped with an automatic angle correction system, known per se, ensuring the horizontality of the platform, regardless of the topography of the terrain. When the horizontal plane is detected, a security system, also known per se, locks the solenoid valves of the jacks constituting the four stabilizing feet.

 The longitudinal elements 6 of the frame 2 are arranged to serve as raceways at the lower movable end of the lower braces of the elevator, which is equipped with a roller.

Stops 7 are arranged between the adjacent extreme portions of the bars 8 constituting the crossbars of the elevator, in order to avoid the jamming effect which the complete "compaction" of the latter could cause in
The folded position. These stops 7 are, for example, constituted by small columns fixed, so
Slightly inclined, on the upper edge of one of the ends of the bars 8 and on the top of which rests the lower edge of the end of the bar arranged in the same plane of the superimposed crosspiece (Figures 5 and 6).

 The deployment and folding of the elevator are obtained by means of hydraulic cylinders 9 or others, operating in synchronism.

 The elevator 1 also comprises an upper frame 10, the longitudinal elements 11 of which are shaped to serve as raceways for the upper movable end of the upper cross-pieces of said elevator, which is equipped with a roller.

 A guide frame 12 is mounted on the frame 10 in an orientable manner.

 This guide frame comprises two parallel rails 13 assembled by crosspieces 14, 14 ', 15.

The guide frame 12 is mounted with a pivotability, for example of an amplitude of the order of 10 degrees, on the upper frame 10 of the elevator 1. This orientable mounting is for example obtained by means of a central pivot 16 fitted to the middle cross member 15 of the guide frame 12, said pivot being housed in a sleeve 17 integral with the middle cross member 18 of the upper frame 10 of
The elevator. A ring 19 surrounding the upper part of the pivot 16 is placed in abutment on an identical ring 20 rigidly fixed on the cross-member 18 and around the inlet of the sleeve 17.

 Each end cross member 21 of the upper frame 10 of the elevator carries a base 22 of arcuate shape on which is placed in abutment a sole 23 secured to one of the intermediate cross members 14 'of the guide frame 12 and having an arcuate shape identical to that of the base 22 (Figures 8 and 9).

 A jack 24 arranged transversely and connected, by means of its opposite ends and by means of articulations and suitable fastening members, on the one hand, to the middle part of one of the intermediate crosspieces 14 'of the guide frame 12 and, on the other hand, at one of the neighboring angles of the upper frame 10 of the elevator, makes it possible to modify the orientation of said guide frame, with respect to said frame.

 In order to relieve the pivot 16 and contribute to the stability of the mounting of the guide frame on the upper frame of the elevator, a clamp 55 grips the superimposed edges of the base 22 and of the sole 23, without preventing the latter from sliding. on said base, under the action of the jack 24. This clamp is for example fixed, by means of its upper jaw 55 ′ and by means of screws, on the upper face of the sole 23.

 At the rear end of the guide frame 12, the nacelle 25 for controlling the installation of actual size is installed.

 On the guide frame 12, is mounted a mobile carriage 26 fitted with rollers 27 and counter rollers 28 allowing its movement on the rails 13, from one end to the other of said guide frame.

This carriage carries a hydraulic motor 29 on the output shaft of which a toothed wheel 30 is wedged in the plane and on each side of which are arranged pinions 31, 32 having a smaller diameter than that of said wheel and mounted for rotation free. Around the upper part of the toothed wheel 30 is wound a fixed chain 33 arranged
Longitudinally and also winding on the lower part of the pinions 31, 32. This chain is secured, by means of its opposite ends, at least one of which is advantageously equipped with a tensioner, at the front and rear ends of the guide frame. It rests in the bottom of a longitudinal gutter 34 carried by the cross members of the guide frame.

 It is understood that the rotation of the toothed wheel 30 in one direction or the other results in a longitudinal translation of the carriage 26, in one direction or the other, that is to say forward or towards the rear of the guide frame 12.

 On the mobile carriage 26, is mounted with an ability to pivot in the horizontal plane, at an amplitude of the order of 90 degrees, an extendable and articulated arm 35.

This arm comprises an extendable main arm 36 advantageously consisting of two tubular elements 37, 38 assembled telescopically, and a secondary arm 39 fixed, by means of a hinge pin 40, to the outer end of the retractable element 38 of said main arm (Figures 13 and 14).

 This orientable arm 35 is mounted on the carriage 26 by means of a vertical axis 41 and its positioning is ensured by a double-acting cylinder 42 fixed, by means of its opposite ends and by means of articulations, of a firstly, to a lever 43 secured to said arm and, secondly, to a fastener 56 secured to the carriage 26 (FIG. 11).

 The jack 42 allows, in the retracted position, to place the arm 35 in a position parallel to the axis of the guide frame 12 and corresponding to the transport position, and, in the elongated position, to bring said arm into a position perpendicular to said axis and corresponding to the working position of the machine.

 A jack 44, housed in the main arm 36, allows the elongation or retraction thereof and, consequently, the elongation or retraction of the whole of the extendable and articulated arm 35. The tubes 37 and 38 constituting the main arm, advantageously have a quadrangular section and the jack 44 is fixed, by means of its opposite ends, on the one hand, to the rear end of the external element 37 and, on the other hand, to L 'front end of the sliding internal element 38 (Figures 7 and 15).

 The secondary arm is mounted with an ability to move between a vertical position, perpendicular to the main arm 36 and allowing vertical cutting, and a horizontal position, parallel to said main arm and allowing horizontal cutting.

 The positioning of the secondary arm is ensured by means of a double-acting cylinder 45 connected, by means of its opposite ends and by means of articulations, on levers or lugs 46, 47 rigidly integral with L ' retractable member 38 of the main arm 36 and the secondary arm 39, respectively.

 On the pivoting secondary arm 39, a cutting head 57 is installed. According to a very advantageous embodiment, this cutting head 57 comprises a tool holder 48 mounted with a pivoting capacity of an amplitude of the order of 174 degrees.

 The reciprocating pivoting movements of the balance formed by this tool holder are obtained, in an interesting manner, by means of a rack-and-pinion cylinder 49 known per se, housed in the tubular secondary arm 39. The rack 50 of this actuated cylinder a reciprocating movement of longitudinal translation, meshes with a toothed wheel 51 wedged on an axis 52 rigidly secured to the tool holder balance 48 (Figures 16 and 17).

 The free end thereof is equipped with at least one cutting member and, advantageously, two rotary cutting members 53, 53 'each driven by an independent hydraulic motor 54, 54' (Figures 17 and 18).

 These cutting members 53, 53 'are arranged in different planes, parallel and close together P-P and P'-P' and they overlap, the edge of one covering the edge of the other.

 Each cutting member comprises a fixed co-utel 58 and a rotary circular counterblade 59 pressed against said knife, so as to produce a cut by shearing.

The fixed knife and the rotary counter-blade of these cutting members are advantageously each made up of a blade-carrier disc on the periphery of which are fixed, in a removable manner, one or more blades or blades. Such cutting members have for example been described in document EP-A-O 147 344.

 The cutting members 53, 53 'are carried by a rigid frame 60 arranged to constitute the extreme portion of the supply and return pipes connected to the hydraulic drive motors 54, 54' of said cutting members.

The size self-propelled platform according to the invention is also provided with various equipment known per se and ensuring the automatic operation of the cutting installation proper and the safety of this operation such as, for example: hydraulic group (tank with filters, strainers, drain valves; gear pumps; pressure relief valves; solenoid valves, bypass mounted on drilled blocks), adjustment controls (solenoid valves with electrical control box and manipulators), safety devices such as valves balancing and non-return valves piloted equipping the cylinders working under load, safety systems preventing any movement of
The lift, the carriage and the arm in the absence of a guarantee of perfect stability of the assembly or of the presence of the operator in the piloting nacelle, devices for detecting the position of different mobile elements of the machine, etc.

 In order to facilitate its alignment with respect to the row of trees to be pruned, the self-propelled pruning platform according to the invention can also be equipped with a receiving cell enabling it to be guided on a reference plane defined by a rotating laser, according to a process known per se.

 An example of the operation of the self-propelled size platform which has just been described is set out below.

A - Horizontal section (figure 20)
The self-propelled platform being immobilized on the ground by means of the stabilizing feet 5, the operator, on board the piloting nacelle 25, controls, successively - the ascent of the lifting platform (upper frame 10 of the elevator 1) above the treetops A; - The pivoting of the orientable arm 35, over 90 degrees, in order to bring it from the transport position to the work position; - the recoil of the carriage 26 in the start of race position, near the nacelle 25; - starting the oscillating balance 48 and the cutting members 53, 53 '; - Adjusting the length of the extendable arm 35, so that the cutting head 53-53 'can cover the entire surface of the block to be cut; - the adjustment of the cutting level, by slightly lowering the lifting platform, to the desired cutting height; the automatic advance of the carriage 26 which moves on the rails 13 of the guide frame 12.

 The alternating semi-circular movement communicated to the cutting head is automatically combined with the advance movement of the carriage 26 moving on the rails 13 of the guide frame 12. These two movements each have an independent and adjustable speed; the pivoting speed of the tool holder balance 48 being for example adjustable by means of a flow regulator, depending on the nature and density of the plants to be cut.

The carriage 26 being immobilized, the cutting head carried by the oscillating balance 48 rotates in the direction of the longitudinal axis of the machine, corresponding to the active stroke of said cutting head, then it performs a pivoting movement in the direction reverse corresponding to its return stroke at the end of which it stops. The carriage advances by a distance programmed according to the cutting surface covered by the cutting head, and the latter performs a new cutting cycle, and so on, until the carriage arrives at the opposite end of the guide frame. After the return of the cutting head following its last active pivoting movement and ending the pass, the carriage is returned to its starting point, under the control of
The operator.

 If the size of the crown cannot be produced in a single pass, a new pass is carried out, after having adjusted the extendable arm 35 to the desired length to cover the width of the strip remaining to be cut.

 It is observed that the orientable mounting of the guide frame makes it possible to remedy any defect in alignment of the self-propelled platform, so that the axis of movement of the carriage is always parallel to the alignment of shafts.

B - Horizontal section (figure 21)
We proceed in the same way to cut the side of the massif, after having placed the secondary arm 39 in the vertical position, by means of the jack 45, so that the tool-carrying pendulum 48 and the cutting members 53-53 'of the cutting head 57 are also arranged in vertical planes.

 Pruning is carried out by successive passages covering strips of length corresponding substantially to the length of the guide frame and progressing from bottom to top.

 The cutting members mounted at the end of the oscillating tool-carrying pendulum describe a semi-circular trajectory in the vertical cutting plane and cut the vegetation during their pivoting movement from top to bottom. We observe that this movement reproduces, in slow motion, the flail movement of traditional tools, but by cutting a much larger number of branches during each active movement.

 As with horizontal cutting, the carriage 26 advances over a distance programmed as a function of the cutting surface covered by the pivoting of the cutting head, after each back and forth stroke of the oscillating tool-carrying arm 48.

 Each passage cuts a wide strip, the width of which depends on the diameter of the cutting members.

 When a strip has been cut, the lifting platform is mounted to a height corresponding substantially to the cutting width obtained by means of the oscillating cutting head, and a new strip is cut above the previously cut strip, and so on, to the top of the massif.

 When the horizontal cutting and vertical cutting sequence is completed, the self-propelled platform is advanced to the next cutting area, to allow a new cutting sequence to be carried out.

Claims (10)

1. - Machine for pruning curtain trees, preferably executed in the form of a self-propelled platform, characterized in that it comprises an elevator (1) whose upper part (10) is equipped with a chassis guide (12) carrying a movable carriage (26) provided with an articulated arm (35) on the pivoting end part (39) of which a cutting head (57) is fixed. 2. - Machine according to claim 1, characterized in that the guide frame (12) is mounted with a pivotability, on the upper part (10) of the elevator (1). 3. - Machine according to one of claims 1 or 2, caractériSée in that the articulated arm (35) is mounted on the mobile carriage (26) with a pivotability. 4. - Machine according to any one of claims 1 to 3, characterized in that the articulated arm (35) is extensibLe, said arm comprising, for example, a main arm (36) consisting of two tubular elements (37, 38 ) assembled telescopically. 5. - Machine according to any one of claims 1 to 4, characterized in that the cutting head (57) comprises a tool-carrying pendulum (48) fixed, with an alternative pivoting ability, on the pivoting end portion ( 39) of the articulated arm (36-39), and provided with at least one cutting member (53, 53 '). 6. - Machine according to claim 5, characterized in that the reciprocating pivoting movements of the tool-carrying pendulum are ensured by a rack cylinder (49) housed in the pivoting end portion (39) of the articulated arm (35) and of which the movable rack (50) meshes with a toothed wheel (51) wedged on an axis (52) rigidly secured to the tool holder balance (48). 7. - Machine according to any one of claims 1 to 6, characterized in that the cutting head (57) comprises two circular cutting members (53, 53 ') arranged in different planes, parallel and close together (PP, P'-P '), the edges of said cutting members being placed in overlap. 8. - Machine according to claim 7, characterized in that the rotary cutting members (53, 53 ') are of the type comprising a fixed knife (58) and a rotary circular counter blade (59) pressed against said knife, so as to produce a cut by shearing, said knife and counter-blade being preferably each constituted by a blade-carrying disk on the periphery of which are fixed, in a removable manner, one or more blades or counter-blades.  9. - Machine according to claim 1, characterized in that the mobile carriage (26) carries a motor (29) on the output shaft of which is wedged a toothed wheel (30) on which is wound a fixed chain (33 ) arranged longitudinally and secured, via its opposite ends, to the front and rear ends of the guide frame. 10. - Machine according to claim 9, characterized in that the fixed chain (33) rests in the bottom of a longitudinal gutter (34) carried by the guide frame (12).