EP0362098B1 - Shears for crushing concrete - Google Patents

Abstract

A concrete crusher of the type comprising a rotatably mounted frame carrying both the crusher forming members and the shearing members, and wherein said shearing members are formed by at least one fixed arm and one of the arms of the crusher, the latter arm being articulated to said frame and adapted so as to give to the shears the maximum opening when it is in a maximum closed position of the crusher.

Description

The present invention relates to a concrete breaker pliers.

This type of tool is used for the demolition of reinforced concrete structures and generally mounted at the end of the boom of a hydraulic shovel instead of a bucket.

These devices generally consist of a jaw with two arms fitted with teeth, articulated on a frame which is itself rotatably mounted and further comprise a shear arranged between the arms and capable of cutting the irons and other metal fittings.

These systems, in particular the shears, are impractical to use and ineffective. Indeed, the shears are located at the bottom of the jaw and in the immediate vicinity of one of the arms of the jaw which constitutes one of the two sectioning members of said shears.

Such an arrangement has various drawbacks.

The introduction of the irons to be cut inside the shears is difficult because the latter is located at the bottom of the pliers in a place which is very difficult to see from the control cabin of the machine; in addition, the opening of the shears is very small so that it is necessary to work, most of the time, blind, grope to engage the irons and to repeat it several times to cut a bundle of irons. Finally, the maximum opening of the shears being obtained by the maximum opening of the pliers, this can pose serious problems when it is necessary to cut irons in small, congested or narrow access spaces.

Furthermore, from document GB-A-2,071,053 there is known a clamp provided with a shear which, unlike the previous devices, is mounted on the external flank of one of the two articulated arms constituting the clamp.

This device is not more satisfactory because the size of the clamp is substantially increased and the handling of the shears is not practical because it is offset completely outside the clamp, laterally to one arms of the latter. In addition, two independent control systems must be provided, one using pliers, the other using shears.

Document DE-A-2,722,258 also discloses pliers provided with shears. However, it is a device comprising a common, fixed jaw arm, cooperating with a gripper arm and a shear arm arranged in parallel and controlled independently.

The opening of such a device is necessarily limited and it is also necessary to provide two independent systems for controlling the pliers and the shears.

The object of the present invention is to overcome these various drawbacks by proposing another combination of means ensuring both the function of concrete clamps and the shears function, in a much more practical and efficient manner.

To this end, the subject of the invention is a concrete breaker clamp of the type comprising a frame mounted to rotate, carrying both two clamp arms, at least one of which is movable relative to the frame and shearing members, characterized in that said frame is formed of two flanges and in that the shearing members are mounted, on the one hand, on at least one fixed arm formed by an extension of one of the flanges and, on the other hand, on said movable arm of the clamp, said fixed and movable arm being in side-by-side position in the position of maximum opening of the clamp, so as to give the shears its maximum closure in this position.

Such a device is much easier to handle and effective because the shears are located at the end of the pliers and no longer at the bottom or on the external lateral side of the pliers. Its opening is much larger and corresponds to the minimum spacing of the clamp, which makes it possible to shear in one go, after a direct, frank and without engagement groping, several grouped irons. Finally, a single cylinder controls both the pliers and the shears.

The invention also aims to improve the efficiency of the shears and pliers organs by allowing easy adjustment and / or replacement of the blades or teeth.

• Figure 1 représente schématiquement une vue en élévation latérale d'une pince-cisaille selon l'invention, suivant un premier mode de réalisation, la pince étant en position de fermeture maximale ;
• Figure 2 illustre le dispositif de la figure 1 en position d'ouverture maximale de la pince ;
• Figure 3 est une vue en perspective de la pince-cisaille de la figure 1 ;
• Figure 4 est une vue en perspective d'une variante de réalisation dans laquelle la cisaille comporte deux bras fixes jumelés et un bras mobile ;
• Figure 5 est une vue en perspective d'un autre mode de réalisation dans lequel la pince et la cisaille ont un seul bras mobile qui est commun ;
• Figure 6 représente, également vue en perspective, une variante du dispositif de la figure 5 dans laquelle la cisaille comporte deux bras fixes jumelés ;
• Figure 7 illustre le profil et le montage des lames de coupe de la cisaille, et
• Figure 8 illustre l'agencement des dents de la pince brise-béton.

Other characteristics and advantages will emerge from the following description of embodiments of the device of the invention, description given by way of example only and with reference to the appended drawings in which:

• Figure 1 schematically shows a side elevational view of a shear forceps according to the invention, according to a first embodiment, the forceps being in the maximum closed position;
• Figure 2 illustrates the device of Figure 1 in the maximum open position of the clamp;
• Figure 3 is a perspective view of the wire cutter of Figure 1;
• Figure 4 is a perspective view of an alternative embodiment in which the shears comprises two twin fixed arms and a movable arm;
• Figure 5 is a perspective view of another embodiment in which the pliers and the shears have a single movable arm which is common;
• Figure 6 shows, also in perspective, a variant of the device of FIG. 5 in which the shears comprise two twin fixed arms;
• Figure 7 illustrates the profile and mounting of the shear cutting blades, and
• Figure 8 illustrates the arrangement of the teeth of the concrete breaker pliers.

The concrete breaker pliers illustrated in FIGS. 1 to 3 comprises a frame 1 formed by two flanges 2 and 3 on and between which two arms 4 and 5 concrete breakers are articulated.

The assembly 1-5 is mounted infinitely rotatable, by hydraulic motor and rotating joint, on an adapter part 6 of conventional design, intended to be mounted, in the known manner, at the end of the boom of a shovel mechanical for example. Between the part 6 and the frame 1 is interposed the rotation device with its fixed ball ring 7; hydraulic regulation supporting untimely efforts on the rotation control assembly.

The arms 4 and 5 constitute levers flanked by pins 8 and 9 engaged in bearings 10 produced in the two flanges 2 and 3.

One of the ends of the arms 4 and 5, on the inner side, carries teeth 11 mounted removably, while between the other ends of said arms is arranged a double-acting hydraulic cylinder 12 interposed between the flanges 2 and 3.

The angular movement of the arms 4 and 5 is limited by a stop 13 integral with the frame 1 and an arcuate opening 14 formed in each arm and in which the stop 13 can slide.

One of the flanges (2) has, on one side, an extension in the form of an arm 14, the end of which constitutes one of the arms of a shear, the other arm of which is formed by the arm 5 of the pliers .

The active members of the shears consist of cutting blades 15 and 16 mounted removable respectively on the flanks opposite the arms 5 and 14 respectively.

The arrangement of the arm 14 is such that in the position of maximum closing of the clamp (4, 5) as illustrated in FIGS. 1 and 3, the opening of the shears (5, 14) is maximum, while in the maximum open position of the clamp (Figure 2), the shears are completely closed. The blades 15 and 16 are arranged at the ends of the arms 5 and 14 in order to grip the irons with the largest possible opening and greater ease of access to and grip of the irons.

FIG. 7 illustrates the shape and mounting of the blades 15 and 16. These consist, in accordance with the invention, of an elongated plate provided on one of its faces with a series of teeth 17 whose profile asymmetrical is determined so as to retain the irons in the shears and prevent them from sliding outside when the arms 5, 14 are closed. This makes it possible to effectively cut the irons, individually or in groups. To this end, each tooth 17 comprises a side 17a substantially vertical, with respect to the general plane of the blade plate, a side 17b slightly inclined towards the outside of the shears and a heater 17c for connection between the two sides 17a. , 17b, avoiding any sharp edge and therefore fragile at the end of the teeth.

The removable mounting of the blades 15 and 16 allows a re-sharpening of the cutting edge by grinding one of the lateral sides of the blades.

Lateral adjustment of the blades 15 and 16 on the arms 5, 14 is possible thanks to elongated holes 18 made in the blades and in which are engaged fixing bolts.

The teeth 11 of the concrete breaker are preferably made up of parts (FIG. 8) comprising a frustoconical anchoring foot 19 engaged in a housing of corresponding shape formed in the receiving arm (4, 5) and retained in place by a group 20 This assembly makes it possible to transfer onto said frustoconical housing all of the forces exerted on the tooth 11, the external part 21 of which is slightly set back from the face opposite the support arm.

The removable nature of the teeth 11 and of the blades 15, 16 makes it possible to replace damaged parts and possibly to replace current parts with parts of characteristics (shape, nature of the material) better suited to the work envisaged. Currently this is not possible, especially with the teeth of known concrete breakers, which are formed of deposits of weld superimposed on the arms of the pliers, these teeth must also be periodically regenerated due to wear. It should be noted that with the device of the invention when the concrete breaker pliers (4, 5) has completely broken for example a reinforced concrete beam, it is then in the fully closed position (Figure 1), the shears (5, 14) being in the maximum open position and therefore immediately ready to grip and cut reinforcing bars. On the contrary, with the known pliers it is necessary to open the pliers completely since the shears are at the bottom thereof. Similarly, at the end of shearing, the clamp is in the maximum open position, therefore ready to intervene.

It should also be noted that, in the clamp of the invention, the bottom of the clamp (between the teeth 11 and the frame 1) is clearly clear, unlike known devices, which makes it easier to grip and work the clamp.

The end of travel stops (13, 13 ') are necessary, since the arms 4 and 5 are free to rotate, so that in their extreme open and closed positions, said arms 4 and 5 are symmetrical by relative to the axis of the pliers and that the shears are doing their job properly.

FIG. 4 illustrates a variant of the device of FIG. 3 according to which a second arm 14 ′, parallel to the arm 14, is provided by means of an extension of the flange 3. This arm 14 ′ is provided with a blade section 16 ′ parallel to the blade 16, the arm 5 of the clamp moving between the two fixed arms 14, 14 ′.

In the embodiment of FIG. 5, the concrete breaker pliers comprises a movable arm 5 also constituting one of the elements of the shears, exactly as in the embodiment of FIG. 3, but this arm 5 cooperates with a arm 4 ′ fixed, no longer mobile, and formed from an extension of the two flanges 2 and 3.

The cylinder 12 for controlling the arm 5 is anchored at 22 to the frame 1.

Finally, Figure 6 illustrates a variant of the device of Figure 5 in which the fixed arm 14 of the shears is lined with a second fixed arm 14 ′ as in the embodiment of Figure 4, the frame 1 thus having a general shape of U.

In general, the invention is obviously not limited to the embodiments shown and described above, but on the contrary covers all variants thereof, in particular as regards the shapes and arrangements of the blades 16, the teeth 11 and the various arms 4, 5, 14, 4 ′, 14 ′.

Claims (9)

1. Concrete-breaking nippers, of the type having a support (1) mounted so as to rotate, carrying both two nipper arms (4, 5), at least one of which (5) is movable with respect to the support, and shearing members (15, 16, 16'), characterised in that the said support is formed by two plates (2, 3) and in that the shearing members are mounted, on the one hand (16, 16'), on at least one fixed arm (14), formed by an extension of one (2) of the plates, and on the other hand (15), on the said movable arm (5) of the nippers, the said fixed arm (14) and movable arm (5) being side by side in the maximum opening position of the nippers, so as to give the shearing tool (5, 14) its maximum closure in this position.
2. Concrete-breaking nippers according to Claim 1, characterised in that the two arms of the nippers (4, 5) are articulated on the support (1).
3. Concrete-breaking nippers according to Claim 1 or 2, characterised in that the two arms of the nippers (4, 5) form levers whose ends which are opposite to the ends equipped with crushing teeth (11) are connected by a double-acting hydraulic cylinder (12), the said levers being mounted so as to rotate freely on the support (1) and equipped with stops (13, 13') limiting the angular movement of the said arms.
4. Concrete-breaking nippers according to one of Claims 1 to 3, characterised in that the said fixed arm (14) is replicated by a parallel second fixed arm (14'), the said arm (5), which performs the functions of concrete breaker and shearing tool, being mounted so as to be movable between the aforesaid two arms (14, 14').
5. Concrete-breaking nippers according to Claim 1, characterised in that the arm of the nippers (4') other than the one (5) performing the concrete breaker and shearing tool functions is fixed.
6. Concrete-breaking nippers according to Claim 5, characterised in that the said fixed nipper arm (4') consists of an extension of the plates (2, 3) for mounting the nipper arms (4, 5).
7. Concrete-breaking nippers according to Claim 5 or 6, characterised in that the fixed arm (14) forming one of the components of the shearing tool is replicated by a parallel second fixed arm (14'), the said nipper arm (5) performing the functions of concrete breaker and shearing tool being mounted so as to be movable between the aforesaid two arms (14, 14').
8. Concrete-breaking nippers according to one of Claims 1 to 7, characterised in that the cutting blades (15, 16, 16') of the shearing tool are detachable and consist of plates with teeth (17) with an asymmetrical profile (17a, 17b) mounted so as to be adjustable in position on the arms (5, 14, 14').
9. Concrete-breaking nippers according to one of Claims 1 to 8, characterised in that the arms (4, 4', 5) of the nippers carry teeth (11) having anchoring bases (19) held in place by pins (20) in housings of an appropriate shape bearing all the forces exerted on the said teeth (11).

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