APPARATUS FOR ADJUSTING THE POSITION OF A TOGGLE BLOCK OF A JAW CRUSHER, AND USE OF THE APPARATUS

Abstract: A toggle block position adjusting method for a jaw crusher capable of carrying out the adjustment of the position of the toggle block over a wide range without making a device larger and applicable to a large-sized crusher, and a device for use in the method. A technique for adjusting the position of a toggle block of a jaw crusher for use in a method for adjusting the position of a toggle block supporting one end of a toggle plate which is connected to a lower end portion of a swing jaw at the other end thereof, the method being implemented with a device having a push-out block positioned on the back side of the toggle block and adapted to be moved in a direction in which the toggle block is moved back and forth and a pair of hydraulic cylinders connected at one end thereof to the ends of the toggle block located in a direction perpendicular to a direction in which the toggle block is moved back and forth and adapted to be extended and contracted in a direction in which the toggle block is moved back and forth, the method comprising the steps of advancing the push-out block to thereby push out the toggle block toward the toggle plate, causing the hydraulic cylinders to contract to thereby pull in the toggle block, and inserting a shim in a gap produced between the back of the toggle block and the front of the push-out block.

Description: Field of the Invention This invention relates to an apparatus for adjusting the position of a toggle block in a double toggle or single toggle jaw crusher, and the usage thereof. Prior Art A jaw crusher is a typical crushing machine that can be used for the primary breaking of rocks as excavated. An example of a double toggle jaw crusher is shown in Fig. 3. Excavated rocks are scooped into a crushing cavity 12 formed between a fixed jaw 1 and a swinging jaw 11, and are broken by the impelling force of the swinging jaw 11. The swinging jaw 11 is suspended from a swinging jaw shaft 13 serving as a fulcrum, and swings with the movement of a pitman 21 moving up and down with the rotation of an eccentric shaft 2, and a toggle mechanism on either side of the pitman 21. In this case, a double toggle mechanism is formed by a jaw toggle plate 22 that connects the swinging jaw 11 and the pitman 21, and a frame toggle plate 24 that connects the pitman 21 and a toggle block 23. A safety device forming a guard against uncrushable objects, and an adjustment device to adjust the gap between the fixed jaw 1 and the swinging jaw 11, thereby controlling the degree of crushing, are set on the side of the frame toggle plate. This cavity width adjustment device slides the toggle block 23 back and forth by the movement of a wedge 25, and by means of the frame toggle plate 24, the pitman 21, and the jaw toggle plate 22, adjusts the forward and backward position of the swinging jaw 11. A single jaw crusher has neither a pitman 21 nor a jaw toggle plate 22, and the eccentric shaft 2 serves a dual function as the swinging jaw shaft 13. As described above, a wedge 25 is conventionally pushed in to slide the toggle block 23, but such a configuration restricts the range of adjustment, and is difficult to apply to a large jaw crusher. In order to obtain a wider adjustment range, the dimensions of the sliding mechanism, including the wedge, would have to be enlarged, necessitating an enlargement of the entire jaw crusher configuration. Document JP 57 144 043 A discloses in figure 2 a jaw crusher in which a displacement block 16 moves in the same lateral direction as a toggle block 6 and is positioned on the rear face of the toggle block. The toggle block 6 and the displacement block 16 are displaced by a wedge 15. To enlarge the adjustment range of the cavity width of a jaw crusher it is known from US 2,566,538 to insert shims beween a toggle block and a back plate. To make it easier to adjust the cavity width of the jaw crusher hydraulic cylinders are provided to pull forward the toggle block so that shims can be inserted into a gap formed between the toggle block and the back plate. The object of this invention is to provide an apparatus for adjusting the position of a jaw crusher toggle block, wherein the apparatus can adjust the cavity width over a wide range, and can be applied to a wide range of jaw crushers, including large models, without having to be enlarged itself. Disclosure of the Invention The invention provides an apparatus for adjusting the position of a toggle block of a jaw crusher in which the toggle block supports the one end of a toggle plate that is connected at the other end to the bottom of a swinging jaw, wherein the apparatus comprises a displacement block that is positioned on the rear face of the toggle block and moves in the same lateral direction as the toggle block, and is characterized in that a pair of hydraulic cylinders is connected to the toggle block at the two end that lie perpendicular to its lateral direction of motion in such a manner that, in the lateral direction of motion of the toggle block, the hydraulic cylinders are contracted if the displacement block advances and displaces the toggle block forward, and are expanded and push back the toggle block if the displacement block is moved backwards, wherein the hydraulic cylinders bear a specified percentage of the load required to move the toggle block and the balance of the load is borne by the displacement block and wherein in forward direction, when the displacement block reaches its limiting position, the hydraulic cylinders are further contractable to advance the toggle block and to cause a gap between the planar face of the displacement block and the rear face of the toogle block, in which a suitable number of shims is insertable. In the jaw crusher toggle block sliding device, the displacement block comprises a planar face that contacts the rear face of the toggle block, and a tapered segment formed by sloped faces on the reverse side of the planar face, wherein a wedge interlocking with the tapered segment is movable in a direction perpendicular to the lateral movement of the toggle block, thereby causing the displacement block to move forward or backward. Also, in the jaw crusher toggle block sliding device, the displacement block comprises a planar face that contacts the rear face of the toggle block, and a pyramid segment formed by two sloped faces on the reverse side of the planar face, wherein two wedges interlocking with each sloped face are movable towards each other or apart from each other, in a direction perpendicular to the lateral movement of the toggle block, thereby causing the displacement block to move forward or backward. Moreover, in the jaw crusher toggle block sliding device, relief valves are set in a hydraulic fluid circuit of the hydraulic cylinders, wherein the relief valves are adjusted such that the hydraulic cylinders will bear a specified percentage of the load required to move the toggle block, and the balance of the load is borne by the displacement block. Given the configuration and action as described above, the invention is effective in that once the displacement block reaches its limiting position, the hydraulic cylinders are contracted to further pull the toggle block forward, wherein a gap is formed between the planar face of the displacement block and the rear face of the toggle block, into which a suitable number of shims is inserted. Such a configuration enables the position of the toggle block to be adjusted over a wide range without having to enlarge the dimensions of the adjustment device, and can even be applied to large jaw crushers. Brief Explanation of the Drawings Figure 1 is a schematic explanatory diagram of an embodiment of the device of this invention. Figure 2 is an explanatory diagram of the entire configuration of an embodiment of the device of this invention. Figure 3 is an explanatory diagram of a conventional technique. Detailed Description of Preferred Embodiments An example of an embodiment of this invention is explained below with reference to the drawings. This explanation is for a double toggle jaw crusher, but the invention can also be applied to a single toggle jaw crusher. Configuration of the Toggle Block Sliding Device As shown in Figure 2, a toggle block 3 is sandwiched between an upper support member 15 and a lower support member 16, arranged like shelves and joined to a main machine frame 14. The one end of a frame toggle plate 24 is connected to the toggle block 3. During normal crushing operation, this toggle block 3 remains fixed in position. A frame toggle plate 24, a pitman 21, a jaw toggle plate 22, a swinging jaw 11, and a fixed jaw 1 are of conventional configuration, and hence an explanation thereof is omitted here. A cavity width adjustment device is set inside a housing 17 joined to the frame 14 on the rear side of the toggle block 3. This housing 17 is open on that side facing the toggle block 3 and houses a displacement block 4a, a facing block 4b, two wedges 5a and 5b, and a screw rod 6. As shown in Figure 1, the displacement block 4a abuts against the rear face of the toggle block 3, and it comprises a planar face 41 and two sloped sides 42 on the opposite face that form a pyramid. Springs 43 are mounted on either end of the displacement block 4a, each of which is energized in the direction of the facing block 4b. The facing block 4b comprises two sloped sides 42 to form a mirror image of, and set at a specified distance from, the pyramid segment of the displacement block 4a. The wedges 5a and 5b are positioned between the displacement block 4a and the facing block 4b with each wedge being of a shape formed by the two opposing sloped sides 42 thereof. A trapezoidal screw 51 is mounted in the centre of each wedge 5a and 5b, and the screw rod 6 is screwed through the central axis formed by the trapezoidal screws 51 and the wedges 5a and 5b. The one end of the screw rod 6 is connected to a rotating drive motor 61. The one end of two hydraulic cylinders 7a and 7b is connected to each end of the toggle block 3 that is perpendicular to its lateral movement, wherein the hydraulic cylinders expand and contract in the direction of the lateral movement of the toggle block 3. An example of a hydraulic fluid circuit 8a and 8b of the hydraulic cylinder 7a, 7b is shown in Figure 1. Relief valves 81a and 81b, and a switching valve 82 are set in the circuits, and a check valve 83 is set between the hydraulic cylinder 7a of the hydraulic circuit 8a and the relief valve 81a. A hydraulic pump 85 is set on the hydraulic tank 84 side of the hydraulic fluid circuit 8b. Hydraulic fluid circuits 8c and 8d of the other hydraulic cylinders 7b are connected to the hydraulic fluid circuits 8a and 8b, respectively, between the hydraulic cylinder 7a and the relief valves 81a and 81b. The relief valves 81a and 81b can be adjusted such that the hydraulic cylinders 7a and 7b will bear a specified percentage of the load required to move the toggle block 3. In this case, the displacement block 4a can bear the remaining load, thus reducing wear of the rotating drive motor 61 that rotates the screw rod 6. Method for Adjusting the Position of the Toggle Block As the liners of the fixed jaw 1 and the swinging jaw 11 wear out, the cavity width becomes too wide, in which case the toggle block 3 can be moved forward to narrow the gap. In this case, the rotating drive motor 61 is started to rotate the screw rod 6 to drive the wedges 5a and 5b closer together, thereby causing the displacement block 4a to advance and displace the toggle block 3 forward. At the same time the hydraulic cylinders 7a and 7b are contracted, and the two actions together cause the toggle block 3 to advance. When the displacement block 4a reaches its limiting position, the hydraulic cylinders 7a and 7b are contracted further to advance the toggle block 3 to the required position. This action causes a gap to be formed between the planar face 41 of the displacement block 4a and the rear face of the toggle block 3, in which a suitable number of shims are inserted. Accordingly, the impelling force transmitted to the toggle block 3 during crushing can be transferred to the rear side of the toggle block 3. In order to reverse the toggle block 3, the screw rod 6 is rotated in the reverse direction to drive the wedges 5a and 5b apart from each other, and the displacement block 4a is pulled back by the compressive force of the return springs 43. At the same time, the hydraulic cylinders 7a and 7b are expanded to push back the toggle block 3, and the two actions together cause the toggle block 3 to reverse.

Claims: An apparatus for adjusting the position of a toggle block (3) of a jaw crusher in which the toggle block (3) supports the one end of a toggle plate (22, 24) that is connected at the other end to the bottom of a swinging jaw (11), wherein the apparatus comprises a displacement block (4a) that is positioned on the rear face of the toggle block (3) and moves in the same lateral direction as the toggle block (3), characterized in that a pair of hydraulic cylinders (7a, 7b) is connected to the toggle block (3) at the two ends that lie perpendicular to its lateral direction of motion in such a manner that, in the lateral direction of motion of the toggle block, the hydraulic cylinders (7a, 7b) are contracted if the displacement block (4a) advances and displaces the toggle block (3) forward, and are expanded and push back the toggle block (3) if the displacement block (4a) is moved backwards, wherein the hydraulic cylinders (7a, 7b) bear a specified percentage of the load required to move the toggle block (3) and the balance of the load is borne by the displacement block (4a) and wherein in forward direction, when the displacement block (4a) reaches its limiting position, the hydraulic cylinders (7a, 7b) are further contractable to advance the toggle block (3) and to cause a gap between the planar face (41) of the displacement block (4a) and the rear face of the toggle block (3), in which a suitable number of shims (9) is insertable. The apparatus according to claim 1, comprising a suitable number of shims (9) inserted in the gap to adjust the toggle block (3) in a position beyond the limiting position of the displacement block (4a). The apparatus according to claim 1 or 2, wherein the displacement block (4a) comprises a planar face (41) that contacts the rear face of the toggle block (3), and a tapered segment formed by sloped faces (42) on the reverse side of the planar face, wherein a wedge interlocking with the tapered segment is movable in a direction perpendicular to the lateral movement of the toggle block (3), thereby causing the displacement block (4a) to move forward or backward. The apparatus according to claim 1 or 2, wherein the displacement block (4a) comprises a planar face (41) that contacts the rear face of the toggle block (3), and a pyramid segment formed by sloped faces (42) on the reverse side of the planar face, wherein two wedges (5a, 5b) interlocking with each of the sloped faces (42) are movable towards each other or apart from each other, in a direction perpendicular to the lateral movement of the toggle block (3), thereby causing the displacement block (4a) to move forward or backward. The apparatus according to any of claims 1 to 4, wherein relief valves (81a, 81b) are set in a hydraulic fluid circuit (8a, 8b) of the hydraulic cylinders (7a, 7b), wherein the relief valves (81a, 81b) are adjusted such that the hydraulic cylinders (7a, 7b) will bear a specified percentage of the load required to move the toggle block (3), and the balance of the load is borne by the displacement block (4a). Use of the apparatus according to any of claims 1 to 5 in a jaw crusher to adjust the width of the crushing cavity (12) which is formed between a fixed jaw (1) and the swinging jaw (11).

Inventors: KAYA TAKATO, KAYA, TAKATO, KAYA, Takato, Kotobuki Engin. &amp; Manuf. Co. Ltd.
Applicants: KOTOBUKI GIKEN KOGYO KK, KOTOBUKI ENGINEERING & MANUFACTURING CO LTD
Application year: 1995
Main classification: B02C1
IPC codes: B02C1