Device for a crusher

Abstract

The invention relates to a device for a crusher, comprising a frame (2) for a crushing chamber (8), which frame comprises a crossmember (1), the crushing chamber being delimited by a crushing jaw (5), which is drivably connected to a reciprocating piston (4) inserted into a hollow cylinder (3). The aim of the invention is to reduce the material fatigue, the weight and the space requirements of a device of the type described above while achieving the same mechanical stability. This aim is achieved, according to the invention, in that the swept volume of the hollow cylinder (3) lies completely within the crossmember (1).

Description

Technical area

[0001] The invention relates to a device for a crusher with a frame comprising a traverse for a crushing chamber, which is delimited by a crushing jaw which is drive-connected to a reciprocating piston inserted into a hollow cylinder. State of the art

[0002] Various devices for jaw crushers are known from the state of the art. All of them are based on the principle of preventing damage to the jaws of a jaw crusher by retracting the movable jaw from the opposing jaw via a lifting system if a non-crushable object enters the crushing gap.

[0003] The forces caused by such an object can lead to damage to the components involved. Even with a controlled adjustment of the crushing gap width, reaction forces arise due to the inertia of the components, which place stress on the components involved. An important aspect to consider when designing a device is therefore the dissipation and distribution of these unwanted forces from the crushing jaw into the supporting structure of the jaw crusher. In the current state of the art, this is usually achieved via a mechanical connection of the lifting system to a crossbeam, via which the forces are introduced into and distributed by the side walls that form the frame of the jaw crusher.

[0004] EP2662141B1 discloses a support frame with a lifting system, in which the lifting cylinder of the lifting system is supported against the frame's cross member, and stiffening elements are provided in the cross member to dissipate the forces generated. The piston of the lifting system is connected to the movable crushing jaw via a lever.

[0005] US6375105B1 shows a cross member forming a support. This also shows a lifting system with hollow cylinders, in which the hollow cylinders are mounted at their cylinder heads on the side of the support facing away from the crushing chamber. Document EP 2754499A1 discloses a device for a crusher with a frame comprising a cross member for a crushing chamber, which is delimited by a crushing jaw that is drivingly connected to a reciprocating piston inserted into a hollow cylinder.

[0006] The state-of-the-art devices therefore require massive components and a robust connection between the components involved, so that material-to-material connections, solid flanges, or additional stiffening elements are typically provided. These additional elements increase the space requirements, design effort, and maintenance intensity. For example, EP2662141B1 connects the crossbeam to the lifting system centrally rather than at the edge, which requires a recess in the crossbeam for the lifting system. However, this necessary recess requires the crossbeam to be more stable than with edge-mounted mounting, which increases the overall weight. Description of the invention

[0007] The invention is therefore based on the object of providing a device which reduces material fatigue while maintaining the same mechanical stability and is more space-saving and lighter without additional stabilising elements.

[0008] The invention achieves this objective by locating the displacement of the hollow cylinder entirely within the crossbeam. While weakening the crossbeam as described herein fundamentally reduces its mechanical stability, the system pressure prevailing in the hollow cylinder, typically up to 400 bar, results in stiffening, allowing weight to be reduced without mechanical disadvantages. The simultaneous reduction in the overall length of the crossbeam also reduces the lever arm formed by the crossbeam, significantly minimizing transverse forces and thus reducing material fatigue. This means that the hollow cylinder, when installed in the crossbeam, can only be accessed for maintenance purposes via a screwed closure on the side facing away from the crushing jaw.Because the displacement, and thus the piston stroke, are completely within the crossbeam, the overall length of the device from the crossbeam to the drive-connected crushing jaw can be significantly reduced, thereby reducing the space required in the crusher.

[0009] Material fatigue and the space required by the device can be further reduced by having the crosshead with a hollow cylinder recess which, together with the reciprocating piston installed therein, limits the displacement. This eliminates the need for an external cylinder tube and flange as a separate component, thus eliminating mechanical weak points such as welds or similar. This reduces material fatigue and therefore also maintenance costs. Because the hollow cylinder is designed as a recess in the crosshead, the mechanical load on the crosshead is also reduced, as the integrated design means that any forces that occur are evenly transmitted directly via the crosshead into the supporting structure of the jaw crusher, enabling a lighter construction. In addition, the more compact design of the hollow cylinder as a recess in the crosshead enables further weight savings.

[0010] The weight of the crusher can be reduced even further and the replacement of wearing parts made easier if the crossbeam is designed with bearing bodies that engage positively with the bearing mounts of the frame to prevent rotation. Typically, forces and torques are transferred from the device to the crusher frame via a material-to-material connection between the crossbeam of the device and the crusher frame. This not only requires appropriate stiffening of the crossbeam in the connection area, but also requires special treatment of the contact surfaces, for example by heat treatment in the case of welded joints. The form-fitting bearing arrangement eliminates the need for additional material and complex treatment of the contact surfaces, which simplifies production and further reduces weight.Because the crossbeam is rotationally secured via the bearing bodies, the forces and moments to be dissipated are efficiently transferred to the crusher frame even without a material-to-material connection. The positive bearing also enables easier removal and reinstallation of the device, which solves the problem of the design-related difficulty of replacing wear parts. Additionally, force-locking connections can be provided between the crossbeam and frame, for example, to compensate for lateral forces. The crossbeam can be rotationally secured either via at least one rotationally asymmetric bearing body per side or via several rotationally symmetric bearing bodies per side.

[0011] Before an unbreakable object is detected and subsequently retracted by the device, this object, due to its nature, can already cause damage to parts of the crusher. To prevent twisting of the crushing jaw during this time, it is proposed that the crushing jaw be connected to the reciprocating piston so that it can pivot relative to the crosshead about a pivot axis that is essentially parallel to the conveying direction of the crushed material. If an unbreakable object enters the crushing chamber, large local forces act on the crushing jaw. Due to the pivoting connection of the crushing jaw to the reciprocating piston relative to the crosshead, the crushing jaw can immediately, i.e. directly and without active control, perform a compensating movement until the device actively retracts the crushing jaw.Since crusher operation has shown that unbreakable objects in the material flow of the crushed material tend to be located at the edges of the crushing chamber, perpendicular to the conveying direction and perpendicular to the stroke direction, a pivoting bearing arranged centrally on the crushing jaw does not restrict the functional principle described here. In the simplest case, the pivoting bearing can be implemented with hinges or joints. In a particularly preferred embodiment of the device according to the invention, at least partially spherical pressure shells are provided between the crushing jaw and the reciprocating piston, enabling a horizontal rotational movement of the crushing jaw to compensate for the force.

[0012] In order to transfer the force between the crushing jaw and the device more evenly, several hollow cylinders can be provided whose displacements lie entirely within the crosshead and whose strokes can be controlled in groups. Typically, the forces exerted on the crushing jaw by an uncrushable object in the crushing chamber are not evenly distributed across the longitudinal axis of the crushing jaw, which runs perpendicular to the conveying direction. These forces can lead to twisting or even damage to the crushing jaw or the frame. Controlling the strokes in groups means that the relative positions of the pistons to their cylinders can vary during crusher operation and can result in different displacement sizes. This allows unwanted forces to be better dissipated locally because the stroke of the reciprocating pistons, also locally, follows the force distribution along the longitudinal axis.The pistons can be supported either individually on the crushing jaw or via a common element between the reciprocating piston and the crushing jaw. In a particularly preferred embodiment of the device according to the invention, the device comprises three such hollow cylinders, whose strokes lie on a common plane. A particularly effective dissipation of the forces caused by unbreakable objects is achieved if the reciprocating piston is additionally connected to a crushing jaw in such a way that the crushing jaw can be pivoted along an axis parallel to the conveying direction of the crushed material. Brief description of the invention

[0013] The drawing shows an example of the subject matter of the invention. Fig. 1 a side view of a device according to the invention and a crushing chamber, Fig. 2 one of the Fig. 1 corresponding detailed view of the device on a larger scale, Fig. 3 a section along the line III - III of the Fig. 2 and Fig. 4 a perspective view of the device on a smaller scale. Ways to implement the invention

[0014] A device according to the invention comprises a crossbeam 1 mounted in a frame 2. The crossbeam 1 has hollow cylinders 3 whose displacements lie entirely within the crossbeam 1. A lifting piston 4 is inserted into each of the hollow cylinders 3, which is drive-connected to a crushing jaw 5 and forms a lifting system that can be operated, for example, by means of a hydraulic working medium. The drive connection can be established via a predetermined breaking plate 6, which is placed on the lifting piston 4 via a connecting element 7. The crushing jaw 5 is driven by an eccentric and delimits a crushing chamber 8, wherein the position of the crushing jaw 5 and thus the resulting crushing gap can be adjusted by the lifting system.In this case, the crushing jaw 5 can additionally be connected to the frame 2 via a retraction mechanism, such as a spring 9, whose restoring force ensures a continuous connection between the crushing jaw 5 and the cross member 1. As shown in the . Fig. 3As can be seen, particularly preferred design conditions arise when the hollow cylinders 3 are designed as recesses in the cross member 1, since in this case the compressed working medium in the displacement chamber stiffens the hollow cylinders 3 against mechanical loads. If an unbreakable object enters the crushing chamber 8, the forces caused by this object are transferred via the lifting pistons 4, which are drive-connected to the crushing chamber 8, into the cross member 1, from which the forces are introduced into the frame 2 with as little damage to the material as possible and, above all, non-destructively. For this purpose, bearing bodies 10 are provided which form-fit the cross member 1 to the frame 2 as a rotation lock. The lifting pistons 4 can compensate for deformations of the crushing jaw 5 caused by unbreakable objects by means of different stroke paths in their hollow cylinders 3.

Claims

1. Device for a crusher, comprising a frame (2) for a crushing chamber (8), which frame (2) comprises a crossmember (1), which crushing chamber (8) is delimited by a crushing jaw (5) which is drive-connected to a piston (4) inserted into a hollow cylinder (3), characterized in that the capacity of the hollow cylinder (3) lies completely within the crossmember (1).

2. Device according to claim 1, characterized in that the crossmember (1) has a recess as a hollow cylinder (3) which, together with the piston (4) inserted therein, delimits the capacity.

3. Device according to claim 1 or 2, characterized in that the crossmember (1) forms bearing bodies (10) which engage in a form-fitting manner as a means for securing against rotation in bearing receptacles of the frame (2).

4. Device according to claim 1 to 3, characterized in that the crushing jaw (5) is drive-connected to the piston (4) so as to be pivotable relative to the crossmember (1) about a pivot axis substantially parallel to the conveying direction of the material to be crushed.

5. Device according to one of the claims 1 to 4, characterized in that a plurality of hollow cylinders (3) are provided, the capacities of which lie completely within the crossmember (1) and the stroke paths of which can be controlled groupwise.

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