Crusher

Abstract

The present invention relates to a crusher having a crusher unit with a first movable crushing body, a second crushing body assigned to the first crushing body, a crushing gap between the first and second crushing bodies, an overload triggering device coupled to the first or second crushing body having a hydraulic cylinder, the overload triggering device allowing movement of the coupled crushing body to increase the width of the crushing gap, a pressure valve having an open position that establishes a fluid transfer connection between a pressure chamber and a low-pressure area, and a closed valve position that blocks this connection. The overload triggering device has a high-pressure valve, which, in its open position, establishes a fluid transfer connection between the pressure chamber of the hydraulic cylinder and the low-pressure area due to an overload condition, and after the overload condition ends, moves to a closed position to block this connection. The triggering pressure required to open the pressure valve is lower than the triggering pressure required to open the high-pressure valve, thereby increasing the productivity and operational safety of the crusher.

Description

Technical Field

[0001] The invention relates to a crusher, in particular a rotary impact crusher, a cone crusher or a jaw crusher, comprising a crusher unit having a first movable crushing body, in particular a rotor or a crushing jaw, wherein a second crushing body, in particular an impact rocker or a crushing jaw is assigned to the first crushing body, wherein a crushing gap is formed between the first crushing body and the second crushing body, wherein an overload triggering device is coupled to the first crushing body or to the second crushing body, the overload triggering device comprising a hydraulic cylinder and being designed to allow a movement of the coupled crushing bodies to increase the width of the crushing gap, wherein the hydraulic cylinder comprises a pressure chamber, and wherein the overload triggering device comprises a pressure valve which, in its open position, establishes a fluid conveying connection between the pressure chamber and a low-pressure area, while in the closed valve position, the pressure valve blocks this connection. Background Art

[0002] DE102017002079B4 discloses an impact crusher in which a variable crushing gap is adjusted between a rotatable rotor and an impact rocker. During normal crushing operation, a material feeder is used to feed the material to be crushed into the rotor. The rotor throws the material onto the impact rocker. The resulting force causes the rock material to break. The rock material is thus crushed to the desired particle size and can fall out of the crusher housing through the crushing gap. However, it is possible to feed non-crushable objects (such as iron parts) into the rotor. This represents a serious overload condition for the impact crusher, particularly with the risk of damage to the crusher in the process. To make this overload condition manageable, a piston-cylinder unit is connected to the impact rocker. This unit can be used to adjust the position of the impact rocker and, therefore, the width of the crushing gap. The piston-cylinder unit includes a gas pressure spring against which the impact rocker rests.

[0003] During normal crushing operation, the width of the crushing gap is set to the desired size. In the event of a severe overload, the gas spring may be compressed, causing the impact rocker to move away. This increases the crushing gap in a pulsed manner. Unbreakable objects then fall through the crushing gap. The width of the crushing gap is then readjusted to the desired size.

[0004] The gas spring proposed in DE 10 2017 002 079 B4 introduces elasticity into the support portion of the impact rocker. During the crushing process, the forces will vary within a certain tolerance due to the varying hardness and size of the rocks. In response to these changing forces, the elastic gas spring causes a constant change in the crushing gap and, consequently, in the particle size of the crushed material, which is undesirable.

[0005] EP 0 019 541 B1 discloses an impact mill in which the crushing gap can be adjusted via a hydraulic damper. The hydraulic damper has a piston to which a piston rod is connected. The piston can be adjusted within a cylinder chamber. The piston rod is connected to an impact rocker. An overload valve is provided in the event of an overload. If uncrushable objects enter the crushing chamber, the overload valve is triggered, increasing the size of the crushing gap and causing the uncrushable objects to fall out of the crushing chamber.

[0006] As already mentioned, in crushers, especially rotary impact crushers, rock materials of varying sizes and hardness are often fed into the crusher unit during normal crushing operation. Rotary impact crushers can handle these rock materials and crush them. In this regard, it is important to distinguish between these less severe cases and severe overload conditions, in which uncrushable objects enter the crusher unit.

[0007] However, this is not possible with known rotary impact crushers. In particular, for safety reasons, the overload triggering device is set so that it triggers even when the load is not severe, although this is not necessarily the case. This behavior reduces the effectiveness of the crushing process. In particular, after a trip, it always takes a certain amount of time for the crusher unit to reset properly. Summary of the Invention

[0008] The problem addressed by the present invention is that of providing a crusher of the above-mentioned type which allows an efficient crushing operation.

[0009] This problem is solved by an overload triggering device having a high-pressure valve, which, due to a severe overload situation, in its open position establishes a fluid conveying connection between the pressure chamber and the low-pressure area of the hydraulic cylinder, and after the overload situation has ended, the high-pressure valve moves into a closed position to prevent this connection, and the problem is solved by the triggering pressure required to open the pressure valve being lower than the triggering pressure required to open the high-pressure valve.

[0010] If short load peaks occur during the crushing operation (for example, due to large rocks in the crushing chamber), this represents an acceptable load condition that the crusher unit can handle. In this case, the crushing gap only needs to be slightly increased to avoid excessive stress on the crusher unit. The large rocks can then be crushed, and the crushed material has a coarser particle size for a short period of time. Incidentally, the setting of the crushing gap can be kept constant even for large variations in the load in the crushing chamber.

[0011] If uncrushable objects (e.g., iron lumps) enter the crushing chamber, this can lead to high load peaks. The overload trigger can then react using the connected high-pressure valve. This significantly increases the crusher's efficiency and operational safety in a simple manner.

[0012] According to a preferred variant of the invention, provision can be made for a triggering pressure of ≦100 bar required to open the pressure valve and a triggering pressure of ≧200 bar required to open the high-pressure valve.

[0013] The inventors have recognized that in crushers, particularly rotary impact crushers, even mild overload conditions can result in pressures in the hydraulic cylinder ranging from 40 bar to 100 bar. Therefore, the trigger pressure for opening the pressure valve can be set to less than 100 bar. It is particularly advantageous to provide for limiting the pressure in the hydraulic cylinder to a range of 50 bar to 65 bar using the pressure valve. In this way, the most common crushing tasks can be optimally performed. In contrast, the required trigger pressure for a high-pressure valve should be set to >150 bar to safely control severe overload conditions. Preferably, depending on the crusher design, the trigger pressure in the hydraulic cylinder should be greater than 200 bar, greater than 250 bar, greater than 300 bar, or greater than 350 bar. Crushers with relatively low crushing capacities tend to be set to lower pressure values, while crushers with higher crushing capacities tend to have higher trigger pressures.

[0014] In a particularly preferred embodiment of the present invention, the crushing body coupled to the hydraulic cylinder is adjusted in such a way that, for an open pressure valve, a first increase in the width of the crushing gap occurs, and the crushing body coupled to the hydraulic cylinder is adjusted in such a way that, for an open high-pressure valve, a second increase in the width of the crushing gap occurs, and it is provided that the first increase in width is smaller than the second increase in width, wherein it is preferably provided that the ratio of the first increase in width to the second increase in width is ≤0.5, particularly preferably ≤0.25.

[0015] This crusher design further enhances its effectiveness. In mild overload situations, the crushing gap is only slightly increased to safely control it. After the mild overload situation ends, the slightly increased crushing gap can be quickly adjusted back to the desired size. On the other hand, in severe overload situations, the crushing gap must be widened very quickly to prevent damage to the crusher unit.

[0016] In particular, the crusher according to the present invention can be designed such that, due to the opening of the first pressure valve, a first quantity of hydraulic fluid enters the low-pressure region via the fluid delivery connection, and due to the opening of the high-pressure valve, a second quantity of hydraulic fluid enters the low-pressure region via the allocated fluid delivery connection, and the first quantity is smaller than the second quantity, wherein preferably, a ratio of the first quantity to the second quantity is provided to be ≤ 0.5, more preferably ≤ 0.25. This simple measure can be used to set the crushing gap to different sizes in two overload situations (non-severe overload and severe overload).

[0017] If the overload triggering device is connected to the hydraulic circuit and the hydraulic fluid discharged via the fluid delivery connection of the high-pressure valve is fed into the hydraulic circuit via a connecting line, the hydraulic fluid can be reused in the event of a severe overload and can then be pumped back into the lines of the hydraulic circuit, for example using a pump.

[0018] According to a possible variant of the present invention, the high-pressure valve may include a piston that can be adjusted between a closed position and an open position against a spring preload, and a pressure piece that, in the closed position, is preloaded by the spring and presses sealingly against the valve seat. The spring can be used to set the trigger pressure required to open the valve. This design of the kit can also be used to use different springs with varying spring rates. By selecting the appropriate spring, the trigger pressure and trigger characteristics of the high-pressure valve can be determined, allowing the valve to be designed for a specific crusher type.

[0019] A possible variation of the present invention can be designed such that the piston has at least one first pressure surface and at least one second pressure surface, so that in the closed position of the high-pressure valve, the hydraulic pressure present in the pressure chamber of the hydraulic cylinder pressurizes the pressure surfaces, so that the projections of the first pressure surface and the second pressure surface form a first projection surface and a second projection surface in a plane perpendicular to the spring preload direction, wherein the surface normal to the first projection surface extends in a direction opposite to the opening movement direction of the piston, and the surface normal to the second projection surface extends in the opening movement direction of the piston, and the area of the first projection surface is larger than the area of the second projection surface.

[0020] This design for a high-pressure valve allows for safe control of high pressures. The closing pressure is determined by the spring's preload and the force generated by multiplying the difference in projected surfaces by the applied pressure. Appropriate selection of the surface difference allows the use of relatively soft springs to securely hold the high-pressure valve in the closed position. This significantly simplifies the design of the high-pressure valve. Furthermore, soft springs such as coil springs can easily achieve leaf spring characteristics. This allows the piston to overcome relatively weak spring forces for long adjustment strokes. Consequently, when trigger pressure is applied, the high-pressure valve opens quickly and fully, allowing hydraulic fluid to exit the hydraulic cylinder in a short period of time. This allows for safe control of severe overload conditions.

[0021] Within the scope of the present invention, it is particularly possible to provide not only a first pressure surface and / or a second pressure surface. Instead, multiple first pressure surfaces and / or multiple second pressure surfaces can be provided. The projection of these multiple pressure surfaces then results in a first total projected surface and a second total projected surface, the first total projected surface having a surface normal in the direction of the piston's opening movement, while the second total projected surface has a surface normal in a direction opposite to the direction of the piston's opening movement. The area of the first total projected surface is then greater than the area of the second total projected surface.

[0022] According to the present invention, it can also be provided that the piston has a first pressure surface or multiple first pressure surfaces, and in the closed position of the high-pressure valve, the hydraulic pressure existing in the pressure chamber of the hydraulic cylinder pressurizes one pressure surface or multiple pressure surfaces, and the projection of the first pressure surface(s) in a plane perpendicular to the spring preload direction forms a first projection surface, wherein the surface normal to the first projection surface extends in a direction opposite to the opening movement direction of the piston, and the piston has at least one third pressure surface, and the projection of the third pressure surface(s) in a plane perpendicular to the preload direction of the spring forms a third projection surface, wherein the surface normal to the third projection surface extends in a direction opposite to the opening movement direction of the piston, and in the closed position of the high-pressure valve, there is no hydraulic pressure in the pressure chamber of the hydraulic cylinder at the third pressure surface, and in the open valve position, a spatial connection is established between the third pressure surface and the pressure chamber.

[0023] When the high-pressure valve is closed, the pressure in the hydraulic cylinder's pressure chamber applies pressure to the first pressure surface. When the high-pressure valve trips in the event of a severe overload, the piston shifts in its opening direction. The area upstream of the third pressure surface then also comes into spatial contact with the pressure chamber. In this way, high pressure is applied to this third pressure surface. This high pressure generates an additional force at the third pressure surface in the piston's opening direction. This force therefore increases the opening force used to adjust the piston. Once this force becomes effective, the piston experiences additional acceleration, helping to shorten the opening time. This ensures rapid opening of the high-pressure valve in the event of a severe overload. Hydraulic fluid can then flow out of the hydraulic cylinder quickly, and the crushing body can be adjusted to quickly open the crushing gap.

[0024] According to the invention, it can also be provided that the piston of the high-pressure valve has a through-hole, which is particularly designed as a bore and which establishes a spatial connection between an upstream region of the first pressure surface and a fluid region upstream of the second pressure surface. The spatial connection between the two pressure surfaces is established, at least in certain regions, via the piston. Machining can be performed accordingly easily.

[0025] A particularly compact design can be achieved if the piston of the high-pressure valve has a support section against which the spring, designed as a coil spring, is pushed, the piston has a shoulder supporting one end of the spring, and the other end of the spring is supported on a spring retainer, which is part of the valve body into which the piston is inserted. The spring is also secured against warping at the support section.

[0026] One conceivable embodiment of the invention provides that the piston of the high-pressure valve has a guide section which is preferably guided in a sealing manner on the inner wall of the guide body.

[0027] The crusher according to the present invention can be designed so that the valve seat for the piston is formed by a valve element of the guide body, which is preferably designed in the form of a bushing. The guide body is inserted into the mounting portion of the valve body of the high-pressure valve and forms at least one line section through which the hydraulic medium flows from the pressure chamber in the open position of the high-pressure valve. The guide body can be easily manufactured as a separate component. Therefore, the valve seat can be machined to precisely match the guide body.

[0028] In order to achieve a compact design of the high-pressure valve, it can also be provided that the guide body has an inner wall which is spaced apart from the supporting section of the piston and that the spring is accommodated in the spaced-apart region.

[0029] According to the invention, it can also be provided, for example, that the high-pressure valve comprises a coupling and a valve body, which are connected to one another via connecting ends, that the coupling and the valve body define a pressure relief chamber in the region of these connecting ends, and that, in the open position of the high-pressure valve, the pressure relief chamber establishes a fluid-conducting connection between the pressure chamber of the hydraulic cylinder and the discharge of the high-pressure valve. In the event of a severe overload, after opening the high-pressure valve, the pressure relief chamber can rapidly absorb large quantities of hydraulic fluid, which can then be discharged via the discharge. Since the pressure relief chamber is located in the region of the connecting ends, it can be easily manufactured.

[0030] If the high-pressure valve has been moved to its open position, hydraulic fluid could inadvertently enter the chamber area separated from the pressure area of the high-pressure cylinder by the piston. This hydraulic fluid could potentially impede the free adjustment of the piston. To reliably ensure the reliable function of the high-pressure valve, a drain can be provided that connects the piston of the chamber, which is spatially separated from the pressure chamber of the hydraulic cylinder, to the low-pressure area. The chamber area can preferably accommodate the spring for preloading the piston in a space-saving manner.

[0031] If a displacement sensor is provided to measure or detect the position of the piston, the operating position of the high-pressure valve can be monitored. This allows, for example, the detection of an overload situation. After the overload situation has ended, the displacement sensor can be used to detect the closed position of the piston. The machine control system can then be prompted to return the hydraulic cylinder to its operating position.

[0032] If the pressure valve and the high-pressure valve are connected to the hydraulic cylinder to form one unit, the unit can be easily and quickly installed or replaced in the event of damage.

[0033] Particularly preferably, a control device is provided which, after the overload situation has ended and the pressure valve and the high-pressure valve have been closed, fills the hydraulic cylinder with hydraulic fluid in such a way that the hydraulic cylinder returns to its operating position, forming the crushing gap in the operating state. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The present invention will be explained in more detail below based on the embodiments shown in the accompanying drawings. In the accompanying drawings:

[0035] Figure 1 shows a perspective view of a crusher unit of a rotary impact crusher;

[0036] Figure 2 and Figure 3 Shown according to Figure 1 A schematic diagram of a crusher unit having an overload triggering device;

[0037] Figure 4 Shown according to Figure 2 and Figure 3 A side view of the overload triggering device;

[0038] Figure 5 Shown Figure 4 A perspective view of the overload trigger device;

[0039] Figure 6 The partial cross-sectional view shows the Figure 4 and Figure 5 Isometric view of a high-pressure valve with an overload triggering device;

[0040] Figure 7 Shown according to Figure 6 Detailed side view and cross-sectional view of the high pressure valve;

[0041] Figures 8 to 10 Shown according to Figure 6 and Figure 7 Three different forms of high-pressure valves;

[0042] Figure 11 along Figure 9 The section marked XI-XI in FIG shows the high pressure valve; and

[0043] Figure 12 along Figure 10 The section marked XII-XII in FIG. 1 shows the high-pressure valve. DETAILED DESCRIPTION

[0044] Figure 1 The crusher unit 10 of a rotary impact crusher is shown. The crusher unit 10 comprises a crusher housing in which a movable crusher body 11 is rotatably mounted. The movable crusher body 11 is designed as a rotor. The rotor carries an impact bar 12 in the region of its outer circumference.

[0045] The upper impact rocker 13 is arranged in the inside of the crusher housing. In addition, another crusher body 14 is also arranged in the crusher housing, in this case, this another crusher body forms the lower impact rocker.

[0046] A crushing gap 15 is formed between the rotor (movable crusher body 11) and the lower impact rocker (crusher body 14). As the rotor rotates, the radially outer ends of the impact bars 12 form an outer crushing ring. This crushing ring, together with the opposing surface of the lower impact rocker, forms the crushing gap 15. A rotary bearing 14.1 is used to rotatably mount the lower impact rocker. The width of the crushing gap 15 can be adjusted by the selected rotational position of the lower impact rocker.

[0047] like Figure 1 As further shown, a material feeder 16 can be assigned to the crusher unit 10. This material feeder 16 can be used to convey the material 19.1 to be crushed into the crushing chamber. The conveying direction is Figure 1 As the material 19.1 to be crushed enters the rotor area, the impact rod 12 throws it outward. During this process, the material strikes the upper impact rocker 13 and the lower impact rocker. The material 19.1 to be crushed breaks apart as it strikes the two impact rockers.

[0048] exist Figure 2 and Figure 3 This is shown in more detail in the example of a downstroke rocker. Figure 2As shown in FIG, when the material to be crushed 19.1 hits the crushing body 14, crushed material 19.2 is generated. Once the crushed material 19.2 has a particle size smaller than the crushing gap 15, the crushed material 19.2 falls through the crushing gap 15. It then enters the collection area 17 below the movable crushing body 11 (rotor). Figure 1 As shown in FIG, a conveyor 18 is connected to the collection area 17. This conveyor 18 can be used to remove the crushed material 19.2.

[0049] like Figure 2 As further shown, the hydraulic cylinder 20 is used to support the crushing body 14 relative to the machine structure of the crusher. The support at the machine structure, for example at the machine frame of the crusher, is not shown in detail in the figures. However, Figure 1 The hydraulic cylinder 20 is shown mounted in a largely protected manner outside the crusher housing in which the rotor is mounted.

[0050] like Figure 2 and Figure 3 As shown, the hydraulic cylinder 20 has a cylinder 25 in which a first piston 23 is adjustably guided. The first piston 23 supports a piston rod 22. At its end facing away from the first piston 23, the piston rod 22 has a first coupling 21 with a bearing element 21.1. This bearing element 21.1 serves to connect the first coupling 21 to the bearing 14.2 of the crusher body 14. In this way, the hydraulic cylinder 20 is rotatably mounted to the crusher body 14. The coupling point is located at a distance from the rotary bearing 14.1.

[0051] like Figure 2 As shown, the first piston 23 defines a pressure chamber 24 in the cylinder 25. Hydraulic fluid, in particular hydraulic oil, is filled into the pressure chamber 24. The first piston 23 is supported on this incompressible medium. In this way, the piston rod 22 and the crusher body 14 are held in the Figure 2 In the predetermined crushing position shown in .

[0052] Depending on the crushing task at hand, the working position of the crushing gap 15 must be adjusted accordingly. The crusher has a control device for this purpose. Figure 2 , hydraulic fluid is discharged from the pressure chamber 24. This causes the first piston 23 to move further into the cylinder 25 until the desired crushing gap 15 is set. On the other hand, if a narrower crushing gap 15 is required, additional hydraulic fluid is added to the pressure chamber 24. This moves the first piston 23 while simultaneously increasing the pressure chamber 24. The piston rod 22 continues to move out of the cylinder 25. This causes the crusher body 14 to rotate clockwise, resulting in a narrowing of the crushing gap 15.

[0053] like Figures 1 to 3 As shown, an overload trigger device 30 is also used. The overload trigger device 30 is preferably firmly connected to the hydraulic cylinder 20.

[0054] Figure 4 and Figure 5 The overload triggering device 30 is shown to include a control block for a holding pressure valve. The pressure valve can be formed by a conventional pressure relief valve, which is connected to the pressure chamber 24 on the one hand and to a low-pressure area on the other hand. In this exemplary embodiment, the connection to the low-pressure area is established via a hydraulic line 32. The hydraulic line 32 leads from the pressure valve (control block) 31 to a hydraulic port 33 of the hydraulic cylinder 20. At the end of the first piston 23 facing away from the pressure chamber 24, the hydraulic port 33 opens into the cylinder 25. Figure 2 and Figure 3 In the hydraulic system, the hydraulic fluid is discharged from the pressure chamber 24 and does not fit into the low-pressure chamber of the cylinder 25 due to the volume of the piston rod 22. For example, this discharged hydraulic fluid can be discharged into the hydraulic tank via another pressure relief valve. The pressure valve 31 (and the further pressure relief valve) can be in the form of a simple check valve, which acts in one direction to allow the hydraulic fluid to discharge from the pressure chamber 24.

[0055] Furthermore, a control element can be provided. If the first piston 23 is to be reset, thereby increasing the size of the pressure chamber 24, hydraulic fluid can be introduced into the control element via the hydraulic line 32 and pumped into the pressure chamber 24, bypassing the pressure valve 31. This causes the first piston 23 to move, thereby increasing the pressure chamber 24. The control element can be formed, for example, by a non-return valve acting on the pressure valve 31.

[0056] The pressure valve 31 is set so that it opens when the hydraulic pressure in the pressure chamber 24 is in the range of 50 bar to 100 bar, preferably in the range of 50 bar to 65 bar. This load situation corresponds to an operating situation in which short-term load peaks occur due to the material 19.1 to be crushed. These short-term load peaks can occur, for example, if the material 19.1 to be crushed comprises large pieces of rock. In this case, the pressure valve 31 is triggered. The first piston 23 moves a short distance in the cylinder 25, causing the crushing gap 15 to increase. The rock is then only roughly crushed.

[0057] like Figure 4 and Figure 5 As shown, in addition to the pressure valve 31, a high pressure valve 40 is also provided. Figure 4 and Figure 5As shown, the high pressure valve 40 may also be preferably mounted to the hydraulic cylinder 20 .

[0058] exist Figure 6 and Figure 7 , the high-pressure valve 40 is shown in greater detail in FIG. As can be seen from these figures, the high-pressure valve 40 has a second coupling piece 41, into which the pressure line 43 is integrated. The second coupling piece 41 has attachment mounts 42. In the assembled state, these attachment mounts 42 align with the threaded seats of the hydraulic cylinder 20. In the assembled state, the pressure line 43 is spatially connected to the pressure chamber 24 of the hydraulic cylinder 20 via an opening 43.1.

[0059] The high-pressure valve 40 has a valve body 45, which can be designed similarly to a housing. The valve body 45 forms a connecting end 46. This connecting end 46 can be used to connect the valve body 45 to the connecting end 44 of the second coupling member 41. The connection between the second coupling member 41 and the valve body 45 is established using a screw connection (not shown).

[0060] The valve body 45 has a recess in the region of its connection end 46, which forms a decompression chamber 48. This decompression chamber 48 opens to an outlet opening 48.1, which is located at the bottom of the valve body 45. Figure 10 and Figure 12 Can be seen in.

[0061] The valve body 45 is provided with a mounting portion. A guide body 47 is inserted into the mounting portion. The guide body 47 is preferably cylindrical on its outer circumference. The mounting portion forms an inner cylinder, into which the guide body 47 is inserted in a sealed manner.

[0062] The guide body 47 surrounds a mounting area with an inner wall 47.2. This mounting area also forms a guide surface for the second piston 60, as will be discussed in more detail below. The guide body 47 has a support section 47.1 at its end facing away from the connection end 46. Opposite the support section 47.1, the guide body 47 forms a valve element 47.4 with a valve seat 47.6. A seal 47.5 serves to seal the guide body 47 from the second coupling element 41 in the area of the connection end 44.

[0063] like Figure 7 As shown, the guide body 47 has at least one line section 47.3, which is connected to the decompression chamber 48 in a fluid-conducting manner. To install the guide body 47, it is inserted into the valve body 45 at the end facing away from the connection end 46. The valve element 47.4 limits the insertion movement. Figure 7 As shown in FIG, the valve element 47.4 strikes the second coupling element 41.

[0064] The second piston 60 can be inserted into the guide body 47. The second piston 60 is provided with a guide section 64 on its exterior. This guide section 64 is primarily formed from a cylindrical body, wherein a sealing groove may be formed in the outer circumferential surface of this body. The guide section 64 is held against the cylindrical inner wall 47.2 of the guide body 47 so as to be linearly adjustable in the direction of the central longitudinal axis M of the second piston 60.

[0065] like Figure 7 As shown, the second piston 60 has a pressure piece 65 . In its closed position and therefore in the closed position of the high-pressure valve 40 , the pressure piece 65 of the piston is in sealing contact with the valve seat 47 . 6 of the guide body 47 .

[0066] The second piston 60 forms a first pressure surface 66 and a further second pressure surface 68. The first pressure surface 66 is preferably arranged in the region of the pressure piece 65. Further preferably, the free end of the second piston 60 can form the second pressure surface 68 facing the pressure piece 65.

[0067] Figure 7 The second piston 60 is shown to further comprise a third pressure surface 67 . This third pressure surface 67 is smaller than the first pressure surface 66 , which is arranged further back in the direction of the central longitudinal axis M of the second piston 60 . The third pressure surface 67 is preferably formed by the guide section 64 .

[0068] When the second piston 60 is installed in the guide body 47 , the spring 90 can be inserted from the end facing the connection end 46 into the region between the inner wall 47 . 2 and the support section 62 of the piston.

[0069] In this case, the spring 90 is designed as a coil spring. In the assembled state, one end of the spring 90 rests against the shoulder 63 of the second piston 60. The other end of the spring 90 rests against the support surface 71 of the spring retainer 70. In particular, the spring retainer 70 can be designed as a separate component. After the second piston 60, the spring 90 and the guide body 47 are installed in the valve body 45, the spring retainer 70 is moved to the position indicated by the arrows. Figure 7 , and is screwed to the valve body 45. In the assembled state, the guide body 47 rests against the support section 47.1 on the spring retainer 70, preferably on the support surface 71. In this way, the spring retainer 70 presses the valve element 47.4 of the guide body 47 against the second coupling element 41. The gasket 47.5 is compressed in this process, creating a tight seal. The spring retainer 70 preloads the spring 90 between the support surface 71 and the shoulder 63. This introduces a preload force into the second piston 60. This preload force serves to clamp the piston's pressure element 65 against the valve seat 47.6 of the guide body 47 in a circumferentially tight manner.

[0070] Figure 7 It is shown that the closure element 80 can also be connected in a sealing manner to the spring retainer 70. However, it is also conceivable that the fastener 80 is connected integrally to the spring retainer 70.

[0071] The direction of action of the spring 90 and thus the direction of the preload force acts along the central longitudinal axis M of the second piston 60 .

[0072] The first pressure surface 66 and the third pressure surface 67 are formed so that the projections of these pressure surfaces 66, 67 in a plane perpendicular to the preload direction of the spring 90 form a first projection surface and a third projection surface, wherein the surfaces normal to these first projection surface and the third projection surface are perpendicular to the opening movement of the second piston 60 (in Figure 7 Extending in the opposite direction of (from left to right in the figure).

[0073] The projection of the second pressure surface 68 in a plane perpendicular to the preload direction of the spring 90 forms a second projection surface. A surface normal to the second projection surface extends in the opening movement direction of the second piston 60.

[0074] Now, the design of the second piston 60 is such that when the second piston 60 is closed, Figure 7 As shown in , the area of the first projected surface is larger than the area of the second projected surface. During operation of the high-pressure valve 40, the pressure in the pressure chamber 24 of the hydraulic cylinder 20 is present in the pressure line 43. This pressure is present at the first pressure surface 66. Due to the presence of the through-hole 61, this pressure is also present in the fluid area 72, which is formed upstream of the second pressure surface 68. In this way, this pressure also pressurizes the second pressure surface 68. Now that the first projected surface is larger than the second projected surface, the existing pressure conditions will lift the second piston 60 from the valve seat 47.6. The spring 90 counteracts this behavior. Therefore, the preload force of the spring 90 is selected to compensate for the force exerted in the opening direction of the second piston 60 due to the surface difference, while also applying a residual preload force, which firmly presses the second piston 60 against the valve seat 47.6.

[0075] If a severe overload situation now occurs, the pressure in the pressure chamber 24 of the hydraulic cylinder 20 suddenly increases. This pressure is then also present at the first pressure surface 66 and the second pressure surface 68. If the pressure exceeds a critical threshold value, the high-pressure valve 40 is triggered.

[0076] Depending on the design of the rotary impact crusher, the critical pressure can be selected in the range of greater than 150 bar, greater than 200 bar, greater than 250 bar or greater than 300 bar or greater than 350 bar.

[0077] When this critical pressure is applied, the force acting in the opening direction of the second piston 60 is increased by the forces acting on the first and second pressure surfaces 66 and 68. This force then becomes greater than the preload force of the spring 90. The second piston 60 is then lifted off the valve seat 47.6. Hydraulic fluid can flow from the pressure line 43. The hydraulic fluid flows through the open valve seat 47.6 and into the area upstream of the third pressure surface 67. There, the pressure in the hydraulic fluid causes the force acting on the second piston 60 in the opening direction to increase further. This additional force causes the high-pressure valve 40 to open rapidly.

[0078] The hydraulic fluid can flow through the third pressure surface 67. In this way, it enters the low-pressure range. The hydraulic fluid then enters the decompression chamber 48 through the pipeline section 47.3 and can flow out through the outlet 48.1.

[0079] Preferably, the outflowing hydraulic fluid is collected and returned to the hydraulic system, for example using a tank and a pump.

[0080] When the high pressure valve 40 is triggered in this way, the first piston 23 of the high pressure hydraulic cylinder 20 is pushed into the cylinder 25, thereby reducing the size of the pressure chamber 24. In doing so, a large amount of hydraulic fluid is discharged from the cylinder 25 in a short time. This results in a rapid and extensive increase in the crushing gap 15. This situation occurs in Figure 3 The uncrushable object 19.3 has caused an overload situation. The high-pressure valve 40 has been triggered and the crusher body 14 has been adjusted to form the maximum crushing gap width. The uncrushable object 19.3 can now fall out of the crushing gap 15.

[0081] As soon as the unbreakable object 19.3 falls out of the crushing gap 15, the overload situation no longer exists. The first piston 23 in the high-pressure hydraulic cylinder 20 is no longer loaded by the unbreakable object 19.3. The pressure in the pressure chamber 24 decreases. This causes both the high-pressure valve 40 and the possibly triggered pressure valve 31 to close. When both valves are closed, the machine control system can refill the pressure chamber 24 of the hydraulic cylinder 20 until it reaches its initial position in the operating position ( Figure 2 ).

[0082] Figure 6 A design variant is shown in which a support element displacement sensor 50 is mounted on the high-pressure valve 40. The displacement sensor 50 can be, for example, an inductive sensor. The displacement sensor 50 can determine or detect the position of the second piston 60. This information can be evaluated in the machine control system. Additionally or alternatively, a measuring port 49 for another parameter, such as a pressure gauge or a thermometer, can also be provided. The pressure gauge measures the pressure in the decompression chamber 48.

[0083] like Figure 7As shown, a chamber is formed between the guide body 47 and the second piston 60, in which a spring 90 is arranged. This chamber is further delimited by a guide section 64, which can extend along the inner wall 47.2 in a sealed manner. If a seal were not provided here, or if the seal were not strictly required, hydraulic fluid could enter the chamber when the high-pressure valve 40 is activated. This would hinder the free adjustability of the second piston 60. For this reason, a drain 69 is provided, which is led out of the chamber and into the low-pressure area. Any accumulated hydraulic fluid can then be discharged.

Claims

1. A crusher for mineral or recycled materials, comprising a crusher unit (10), the crusher unit (10) comprising a first movable crushing body (11), a second crushing body (14) being assigned to the first crushing body (11), wherein a crushing gap (15) is formed between the first crushing body (11) and the second crushing body (14), wherein an overload triggering device (30) is coupled to the first crushing body or to the second crushing body, the overload triggering device having a hydraulic cylinder (20), and the overload triggering device is designed to allow a movement of the coupled crushing bodies (11, 14) to increase the width of the crushing gap (15), wherein the hydraulic cylinder (20) has a pressure chamber (24) defined by a first piston (23), and wherein the overload triggering device (30) has a pressure valve (31) which, in its open position, establishes a fluid conveying connection between the pressure chamber (24) and the low-pressure area, while in the closed valve position, the pressure valve (31) blocks this connection; It is characterized in that The overload triggering device (30) has a high-pressure valve (40) which, due to an overload situation, in its open position establishes a fluid conveying connection between the pressure chamber (24) of the hydraulic cylinder (20) and the low-pressure area, and after the overload situation ends, the high-pressure valve (40) moves to the closed position to prevent this connection, and the triggering pressure required to open the pressure valve (31) is lower than the triggering pressure required to open the high-pressure valve (40).

2. The crusher according to claim 1, characterized in that The crusher is a rotary impact crusher or a jaw crusher.

3. The crusher according to claim 1, characterized in that The first crusher body (11) is a rotor or a crusher jaw.

4. The crusher according to claim 1, characterized in that The second crusher body (14) is an impact rocker or a crusher jaw.

5. The crusher according to claim 1, characterized in that The trigger pressure required to open the pressure valve (31) is less than or equal to 100 bar, and the trigger pressure required to open the high-pressure valve (40) is greater than or equal to 150 bar.

6. The crusher according to any one of claims 1 to 5, characterized in that With the pressure valve (31) opened, the crushing body (14) coupled to the hydraulic cylinder (20) can be adjusted to cause a first increase in the width of the crushing gap (15), and with the high-pressure valve (40) opened, the crushing body (14) coupled to the hydraulic cylinder (20) can be adjusted to cause a second increase in the width of the crushing gap (15), and the first increase in width is smaller than the second increase in width.

7. The crusher according to claim 6, characterized in that A ratio of the first increase in width to the second increase in width is less than or equal to 0.

5.

8. The crusher according to claim 6, characterized in that A ratio of the first increase in width to the second increase in width is less than or equal to 0.

25.

9. The crusher according to any one of claims 1 to 5, characterized in that Opening the first pressure valve (31) allows a first amount of hydraulic fluid to enter the low pressure area through the fluid delivery connection, and opening the high pressure valve (40) allows a second amount of hydraulic fluid to enter the low pressure area through the allocated fluid delivery connection, and the first amount is less than the second amount.

10. The crusher according to claim 9, characterized in that A ratio of the first quantity to the second quantity is less than or equal to 0.

5.

11. The crusher according to claim 9, characterized in that A ratio of the first quantity to the second quantity is less than or equal to 0.

25.

12. The crusher according to any one of claims 1 to 5, characterized in that The overload triggering device (30) is connected to the hydraulic circuit, and the hydraulic fluid discharged via the fluid delivery connection of the high-pressure valve (40) is fed into the hydraulic circuit through a connecting line.

13. The crusher according to any one of claims 1 to 5, characterized in that The high-pressure valve (40) comprises a second piston (60) which can be adjusted between a closed position and an open position against the preload of a spring (90) and comprises a pressure piece (65) which, in the closed position, is pressed against a valve seat (47.6) in a sealing manner by the spring preload.

14. The crusher according to claim 13, characterized in that The second piston (60) has a first pressure surface (66) and a second pressure surface (68), and in the closed position of the high-pressure valve (40), the hydraulic pressure present in the pressure chamber (24) of the hydraulic cylinder (20) pressurizes these pressure surfaces (66, 68), and the projections of the first pressure surface (66) and the second pressure surface (68) form a first projection surface and a second projection surface in a plane perpendicular to the preload direction of the spring (90), wherein the surface normal to the first projection surface extends in a direction opposite to the opening movement direction of the second piston (60), and the surface normal to the second projection surface extends in the opening movement direction of the second piston (60), and the area of the first projection surface is larger than the area of the second projection surface.

15. The crusher according to claim 13, characterized in that The second piston (60) has one or more first pressure surfaces (66), which are pressurized by the hydraulic pressure present in the pressure chamber (24) of the hydraulic cylinder (20) in the closed position of the high-pressure valve (40), the first pressure surface (66) being projected in a plane perpendicular to the preload direction of the spring (90) to form a first projection surface, wherein the surface normal to the first projection surface extends in a direction opposite to the opening movement direction of the second piston (60), and the second piston (60) has at least one third pressure surface (67), which is projected in a plane perpendicular to the preload direction of the spring (90) to form a third projection surface, wherein the surface normal to the third projection surface extends in a direction opposite to the opening movement direction of the second piston (60), in the closed position of the high-pressure valve (40), no hydraulic pressure in the pressure chamber (24) of the hydraulic cylinder (20) is present at the third pressure surface (67), and in the open valve position, a spatial connection is established between the third pressure surface (67) and the pressure chamber (24).

16. The crusher according to claim 13, characterized in that The second piston (60) of the high-pressure valve (40) has a passage (61) which establishes a spatial connection between a region in front of a first pressure surface (66) and a fluid region (72) in front of a second pressure surface (68).

17. The crusher according to claim 16, characterized in that The through-hole (61) is designed as a drilled hole.

18. The crusher according to any one of claims 1 to 5, characterized in that The second piston (60) of the high-pressure valve (40) has a support section (62) onto which a spring (90) designed as a coil spring is pushed, and the second piston (60) has a shoulder (63) that supports one end of the spring (90), and the other end of the spring (90) is supported on a spring retainer (70), which is part of the valve body (45) into which the second piston is inserted.

19. The crusher according to any one of claims 1 to 5, characterized in that The second piston (60) of the high-pressure valve (40) has a guide section (64).

20. The crusher according to claim 19, characterized in that The guide section (64) is guided in a sealing manner on the inner wall (47.2) of the guide body (47).

21. The crusher according to any one of claims 1 to 5, characterized in that The valve seat (47.6) for the second piston (60) is formed by a valve element (47.4) of a guide body (47), which is inserted into a mounting portion of a valve body (45) of the high-pressure valve (40) and forms at least one line section (47.3) through which hydraulic medium flows out of the pressure chamber (24) in the open position of the high-pressure valve (40).

22. The crusher according to claim 21, characterized in that The valve element (47.4) is designed in the form of a bushing.

23. The crusher according to claim 21, characterized in that The guide body (47) has an inner wall (47.2) which is spaced apart from the supporting section (62) of the second piston (60), and the spring (90) is mounted in the spaced apart region.

24. A crusher according to any one of claims 1 to 5, characterized in that The high-pressure valve (40) has a second coupling piece (41) and a valve body (45), which are connected to each other via connecting ends (44, 46), the second coupling piece (41) and the valve body (45) defining a decompression chamber (48) in the region of these connecting ends (44, 46), and in the open position of the high-pressure valve (40), the decompression chamber (48) establishes a fluid conveying connection between the pressure chamber (24) of the hydraulic cylinder (20) and the discharge portion (69) of the high-pressure valve (40).

25. A crusher according to any one of claims 1 to 5, characterized in that The second piston (60) of the high-pressure valve (40) spatially delimits a spatial region relative to the pressure chamber (24) of the hydraulic cylinder (20), and the spatial region is spatially connected to a low-pressure region via a discharge portion (69).

26. The crusher according to claim 25, characterized in that A spring (90) is installed in this space area.

27. A crusher according to any one of claims 1 to 5, characterized in that A displacement sensor (50) is provided, and the displacement sensor (50) is used to measure or detect the position of the second piston (60).

28. A crusher according to any one of claims 1 to 5, characterized in that The hydraulic cylinder (20) has a first piston (23) delimiting a pressure chamber (24) in the cylinder region, and a piston rod (22) is coupled to the first piston (23) and is rotatably coupled to the crushing body (14) via a first coupling (21).

29. A crusher according to any one of claims 1 to 5, characterized in that The pressure valve (31) and the high-pressure valve (40) are connected to the hydraulic cylinder (20) to form a structural unit.

30. A crusher according to any one of claims 1 to 5, characterized in that The overload condition has ended and the pressure valve (31) and the high pressure valve (40) have been closed, the hydraulic cylinder is filled with hydraulic fluid to return the hydraulic cylinder to its operating position, forming a crushing gap (15) in the operating state.

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