Abstract:
An improved cone-style rock crusher. The rock crusher may be adjusted for varying rock crushing specifications, including different speeds, throws, and liners. The rock crusher comprises a frame that supports a crushing bowl, a crusher head and a shaft, with the shaft being secured to the crusher head. A domed feed plate may be secured onto the crusher head for assistance in secondary rock crushing processes. An eccentric bushing allows the shaft to be aligned properly, regardless of whether there is a load or not within the crushing bowl. The bushing is tapered downwardly, which allows for evenly dispersed contact along the length of the shaft as it gyrates. Furthermore, the thickness of the bushing is asymmetrical. The rock crusher further comprises uniquely designed tramp release cylinders that provide a safeguard that acts as shock absorbers when the rock crusher encounters tramp material.

Description:
RELATED APPLICATIONS  
       [0001]     This application is a continuation-in-part of patent application Ser. No. 10/861,953, filed on 4 Jun. 2004. 
     
    
     BACKGROUND OF THE INVENTION  
       [0002]     The present invention relates to rock crushers and improved cone-style rock crushers that provide optimal performance for each rock crushing application.  
         [0003]     Numerous rock crushers have been designed to crush and fragment rocks into smaller pieces. Cone-style crushers are a common type of rock crushers. Rocks are fed into the crusher through a rotating feed distributor or on top of the feed plate, which distributes the rocks into a crushing cavity. A crusher head mounted on a shaft is located within the crushing bowl. The shaft rotates or gyrates and crushes the entering rocks. The rocks exit below the crusher and are carried away for further sorting, or to be recycled and reprocessed in the rock crusher.  
         [0004]     However, due to the demanding environment that rock crushers are employed within, repair and maintenance of the rock crushers is common. Much downtime is spent repairing and replacing the components of the rock crusher, including, for example, bearings, bushings, and gearing. Prior art lubrication systems, protection systems and other internal arrangements have not been designed necessarily to optimize the life of the individual parts of the crusher. Repairs not only increase the time required to produce a desired amount of saleable rock products, but also increase the cost of saleable rock products.  
         [0005]     Prior art rock crushers are generally designed for delivering rock products only within a specific size range. If the desired size of the final product is different than the current specifications, the rock crusher generally is not easily modifiable to produce the new product specifications. In prior art rock crushers, it is usually required to change the crushing head and/or the crushing bowl if one needs to change from a coarse secondary crushing arrangement to a fine tertiary crushing arrangement. Similarly, prior crushing bowl designs also did not allow easy changing between different crushing arrangements; variables, such as the throw, speed, and specific liners for specific rock products are not easily changeable in a single rock crusher for multiple rock specifications.  
         [0006]     Thus, an improved rock crusher is needed that will address the above problems and further make operation easier and more efficient for the user. A preferable rock crusher will be able to handle varying product specifications in an efficient manner without requiring extensive retooling or reconfiguring of the rock crusher. Likewise, a rock crusher is needed that will minimize repairs and downtime thereby increasing efficiency and reducing costs for the user.  
       SUMMARY OF THE INVENTION  
       [0007]     The present invention is an improved cone-style rock crusher that will improve the quality and increase the quantity of the end products, while providing an overall more efficient and economical machine to operate. The rock crusher may be adjusted for varying rock crushing specifications, including different speeds, throws, and liners.  
         [0008]     The rock crusher comprises a frame that supports a crusher bowl, a crusher head and a shaft, with the shaft being secured to the crusher head. The crusher head and the shaft are spaced apart and located within the crusher bowl. A domed feed plate may be secured onto the crusher head for assistance in secondary rock crushing processes. The shaft is driven by an electric drive system, which allows the shaft and crusher head to gyrate. An eccentric bushing allows the shaft to be aligned properly, regardless of whether there is a load or not within the crusher bowl.  
         [0009]     The rock crusher further comprises uniquely designed tramp release cylinders that provide a safeguard by acting as shock absorbers when the rock crusher encounters tramp material. The cylinders are part of the release system that allows the crusher to adjust and prevent damage to the crusher components when uncrushable or tramp material enters the crusher bowl.  
         [0010]     Within the rock crusher sits the crusher head and shaft assembly. The assembly rotates or gyrates, which allows a mantle located on the exterior of the crusher head to come in close proximity of the rock crusher bowl for crushing rocks. As the shaft gyrates, especially without rocks in the crushing chamber, the shaft comes in contact with the bushing, which acts as an abutting surface for the maximum outer movement of the shaft. The bushing is tapered downwardly, which allows for evenly dispersed contact along the length of the shaft as it gyrates. Furthermore, the thickness of the bushing is asymmetrical, with the thickness evenly varying from a predetermined maximum thickness to a predetermined minimum thickness. The asymmetrical thickness further provides for an even abutting surface for the shaft to contact. The result is a shaft load that is dispersed over a wide area of the bushing, which virtually eliminates burning of the bushing. In addition, the reduced clearance between the shaft and the bushing creates better hydrodynamic bearing action, resulting in enhanced load capabilities for the bushing. Overall, the combination of the factors improves the reliability of the crusher and the crushing process. In addition the bushing is designed so as to change the crusher throw by changing its geometry.  
         [0011]     The interaction of all of the features of the rock crusher allows the rock crusher to be adjusted to different combinations of speeds, throws and liner combinations, thereby producing more saleable products compared to previous rock crushers. The crusher allows adjustment of the throw and speed of the crusher to be synchronized properly with the horsepower of the crusher&#39;s motor, thereby optimizing the crushing ability of the crusher. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0012]      FIG. 1  shows a perspective view of a rock crusher in accordance with the present invention.  
         [0013]      FIG. 2  is a cut-away perspective sectional view of the rock crusher of  FIG. 1  taken along the line  2 - 2  of  FIG. 1 .  
         [0014]      FIG. 3  is a cross-sectional view of the rock crusher in  FIG. 1  taken along line  3 - 3  of  FIG. 1 .  
         [0015]      FIG. 4  is a close-up cross-sectional view of the drive shaft of  FIG. 3 .  
         [0016]      FIG. 5  is a cut-away perspective cross-sectional view of the drive shaft assembly of  FIG. 3 .  
         [0017]      FIG. 6A  depicts a sectional view of a shaft and bushing in accordance with the present invention.  
         [0018]      FIG. 6B  depicts an overhead view of the shaft and bushing of  FIG. 6A .  
         [0019]      FIG. 7  is a cut-away perspective view of a head assembly in accordance with the present invention.  
         [0020]      FIG. 8  is a close-up cross-sectional view of the head and shaft assembly of  FIG. 3 .  
         [0021]      FIG. 9  is a side view of a tramp release system used in accordance with the present invention.  
         [0022]      FIG. 10  is a cross-sectional view of an adjustment ring assembly according to the present invention used in conjunction with the tramp release system of  FIG. 9 . 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0023]     Although the disclosure hereof is detailed and exact to enable those skilled in the art to practice the invention, the physical embodiments herein disclosed merely exemplify the invention which may be embodied in other specific structures. While the preferred embodiment has been described, the details may be changed without departing from the invention, which is defined by the claims.  
         [0024]      FIG. 1  shows a perspective view of a rock crusher  10  according to the present invention. The rock crusher  10  comprises a mainframe  12 , comprising a base  14  and a body  16 . The body  16  has a first end  18  connected to the base  14  and a second end  20  that supports an adjustment ring  72 . A crusher bowl  24  is assembled into the adjustment ring  72  and is vertically adjustable through its rotation in relationship to the adjustment ring  72 . The crusher bowl  24 , along with a head and shaft assembly  26  that further comprises a crusher head  43  (see  FIG. 3 ), forms a crushing cavity  25  for rock crushing to take place. The head and shaft assembly  26  gyrates to crush rocks as they enter the crusher bowl  24 . A drive assembly  28  provides power means for the head and shaft assembly  26 . A plurality of clamping cylinders  30  secures the adjustment ring  72  to the top end  20  of the frame  12  while crushing occurs, and also provides shock absorption for the rock crusher  10 . The overall arrangement of the rock crusher  10  provides an improved system that maximizes saleable products and minimizes waste by allowing a range of combinations of throw, speed, and liners to maximize the power draw and thus optimize the specific needs of a user.  
         [0025]      FIG. 2  provides a partial sectional view of the rock crusher  10  along the line  2 - 2  of  FIG. 1 . The opening  22  is generally defined by a feed cone  32 , which is held in place by a feed cone adapter  34  and an upper bowl ring  36 . The feed cone  32  is further positioned with the use of an adjustment cap  38 .  
         [0026]     Once rocks enter the opening  22  into the cavity  25  within the bowl  24 , they will encounter a dome feed plate  40  that is supported by a feed plate  42 . The dome feed plate  40  helps to evenly distribute rocks within the bowl  24  and prevents rocks from getting trapped or stuck within the bowl  24 . The feed plate  40  is supported by the head and shaft assembly  26 . The assembly  26  generally comprises the head  43  and the shaft  44 , with the shaft  44  rotating and gyrating within the bushing  46 . The feed plate  40  will be discussed further with respect to  FIGS. 7 and 8 , and the shaft  44  and the bushing  46  will be discussed further with respect to  FIGS. 6A and 6B .  
         [0027]     The head  43  supports a mantle  48 . The crusher bowl  24  supports a liner  52 . The slope of the head  43  is steeper than some designs, which provides for a higher volumetric capacity than in the prior art. A useful angle of the head may be 50 degrees from horizontal. As the head  43  rotates or gyrates, the mantle  48  works together with a bowl liner  52  to provide the necessary surfaces and interaction for rock crushing between the bowl  24  and the head  43  within the cavity  25 . The design of the head  43  and the mantle  48  are of a unique universal design. This design allows use of a single mantle and head for crushing rocks, ranging from a coarse secondary crushing to a fine tertiary crushing, whereas previous rock crushers required changing the head for these different crushing arrangements. Thus, the present invention further saves money and operating time over prior art crushers by minimizing the number of changed parts required for different crushing parameters.  
         [0028]      FIG. 3  provides a cross-sectional view of the rock crusher  10  taken along the line  3 - 3  of  FIG. 1 . The rock crusher  10  is designed so that the bowl liner  52  may be of differing specifications, depending on the needs of the user. However, a preferable bowl liner  52  is designed to maintain a nip angle at 21 degrees or less between the mantle and the bowl liner, which will minimize slippage of the rocks and, thus, wear on the liner  52  and the mantle  48 . Along with the bowl liner  52  and the mantle  48 , the crusher  10  is designed with other liners and devices to provide protection for the crusher  10 . For instance, a socket liner  54  sits upon a socket  56 , with the socket liner  54  providing a seal and bearing for the head  43  when gyrating within the cavity  25 . A frame liner or frame liners  58  are positioned within the frame  12  to protect the frame  12  when rocks are passing through the cavity  25 . An arm guard or arm guards  59  also protect the frame  12  and its components. The arm guards  59  are autogenously designed so that the falling rocks form a dead bed, which further minimizes wear on the supporting arms  69  and, also, minimizes wear to the guards  59 , themselves. The liners  58  are preferably designed of wear resistant steel, thereby minimizing the wear caused by the tumbling rocks.  
         [0029]     Referring to  FIGS. 2 and 3 , the drive assembly  28  comprises a countershaft  60  that provides the means for gyrating the head and shaft assembly  26 . The countershaft sits within a countershaft box  62  and a sheave  64 , which protects the countershaft from dust and dirt. The drive assembly will be discussed further with respect to  FIGS. 4 and 5 .  
         [0030]     Referring again to  FIG. 3 , the body  16  of the frame  12  is generally comprised of a top end that supports the adjustment ring  72  and a bottom half  74 . The clamping cylinders  30  have an upper end  76  connected to the adjustment ring  72  and a lower end  78  connected to base  14  of the frame  12 . The cylinders  30  are connected to a hydraulic power unit (not shown) that provides the necessary means so that the cylinders  30  can act as shock absorbers for the rock crusher  10 . A seat liner  82  and a fulcrum bar  84  are located between the adjustment ring  72  and the top end  20  of the body  16 , which assures that the adjustment ring  72  sits properly on top of the frame  12  and reduces wear on the frame  12 , overall. The seat liner  82 , the fulcrum bar  84 , the cylinders  30  and the hydraulic motor  80  will be discussed in further detail with respect to  FIGS. 9 and 10 .  
         [0031]     The unitary, one-piece molded design of the bottom half  74  of the frame  12  allows adjustment between coarse secondary crushing to a fine tertiary crushing with only needing to change the bowl liner  52 . The bottom half  74  comprises a mounting flange  67 , a central hub  68 , supporting arms  69 , and an outer shell  70 , all of which are cast as a one-piece design. This unitary design gives the crusher  10  extra rigidity and strength to sustain wear and tear associated with overloads that was not previously found in the prior art.  
         [0032]     Referring further to  FIG. 3 , the head and shaft assembly  26  is shown in gyratory fashion, rotating around a central axis Y. As the shaft  44  gyrates around the axis Y, it will come into contact with the bushing  46 , which has an eccentric design. This arrangement allows the throw of the cone crusher, which is the difference of the maximum distance between the bowl liner  52  and the mantle  48  (see, for example, the right side of  FIG. 3 ) and the minimum distance between the bowl liner  52  and the mantle  48  (see, for example, the left side of  FIG. 3 ), to be varied for the rock crusher  10  for the optimization of the production of the saleable rock. Furthermore, to effectively provide full balance for the head and shaft assembly  26  at a wide range of throws and speeds for the crusher  10 , a counterweight  66  is provided that surrounds the eccentric  45  and bushing  46 . The bushing  46  is retained within the eccentric  45  by a key. This is an improvement over the prior art, and the unique design allows quick and easy installation or removal of the bushing  46 , which increases the overall efficiency of the rock crusher  10 . Furthermore, because the crusher  10  can handle a wider range or crushing parameters, the settings may be changed during the crushing process, thereby providing an overall more efficient process.  
         [0033]      FIGS. 4 and 5  depict the drive shaft assembly  28 . The drive shaft or countershaft  60  sits within the countershaft box  62 . The drive shaft  60  preferably does not have any shoulders, grooves, or other sectional changes along the shaft  60 , which increases the strength of the shaft  60 . The drive shaft  60  has a first end  90  and a second end  92  and rotates about an axis X. The first end  90  sits within a locking collar  94  that connects the drive shaft  60  to a pinion  96 . The locking collar  94  is preferably tapered, thereby making the mounting of the pinion  96  on the shaft  60  easier, which makes the assembly and removal process of the drive shaft assembly  28  easier, as well. The pinion  96  in turn is engaged to a gear  98 , preferably a spiral bevel gear, which translates the rotational movement of the drive shaft  60  into the gyrational movement for the head and shaft assembly  26 . The second end  92  of the drive shaft  60  is connected to the sheave  64 . The outside of the sheave  64  is arranged to receive a drive belt or drive belts (not shown) for connection to a motor or other power means (not shown). Tapered roller bearings  100  are used to support the rotation of the shaft  60 . The bearings  100  are designed to effectively carry a load or force in all directions, which provides added flexibility to the assembly  28  in that the drive motor (not shown) may be mounted at different positions. As previously discussed, the arrangement of shaft  44 , bushing  46 , and the counterweight  66 , allows the crusher to be run at a wide range of motor horsepower. The shaft  60  and the bearings  100  are preferably sealed within the countershaft box  62  and lubricated with a static oil bath, thereby minimizing the possibility of dirty oil being used in the assembly  28  and increasing the life of the individual parts of the assembly  28 . Furthermore, the assembly  28  is designed for insertion or removal as a single cartridge, thereby facilitating potential replacement of the drive assembly  28  and allowing for less down time if replacement is necessary. Also, because the assembly  28  preferably is designed as a single cartridge, there is less opportunity for dirt to foul up the individual parts of the assembly  28  when inserting or removing the assembly  28 , and, also, the design provides for a safer drive system than previous crusher designs.  
         [0034]      FIG. 6A  shows a side elevation view of the shaft  44  and the bushing  46  in accordance with the present invention. It is to be understood for the following discussion that the shaft  44  refers to the area of the shaft that comes in contact with the bushing  46 , and not the entire shaft  44 . The shaft  44  is depicted gyrating without a load of rocks in the crushing bowl  24  and cavity  25  (see  FIG. 3 ). As disclosed in  FIG. 6A , the bushing  46  has a top end  110  and a bottom end  112 . The bushing  46  evenly tapers inwardly from the top end  110  to the bottom end  112 , which results in the top end  110  having a first inner diameter ID 1  larger than that of a second inner diameter ID 2 , located at the bottom end of the bushing  46 . The arrangement of the bushing  46  allows the shaft  44  to evenly be in contact along the entire length of the bushing  46 . This removes pinch point that was prevalent in the prior art, which resulted in the force and pressure exerted on the bushing being concentrated at a specific pinch point at the top end of the bushing. The prior are bottom end of the bushing did not make contact with the shaft, and the concentration of force at the pinch point lead to burning of the bushing, which leads to the failure of the bushing and other adverse effects on a rock crusher. In the present invention, the bushing  46  provides an abutment for the shaft  44  that is coextensive along the length of the shaft  44 . Thus, contact between the shaft  44  and the bushing  46  is linearly displaced along the entire length of the shaft  44  as opposed to a single point, with the result being virtually no burning of the bushing  46  and a longer life for the bushing  46 . A longer bushing life equates into less downtime for a rock crusher previously required to replace burnt bushings, which leads to an increase in productivity.  
         [0035]     Still referring to  FIG. 6A , the bushing  46  has a first outer diameter OD 1  located at the top end  110  of the bushing  46  and a second outer diameter OD 2  located at the bottom end  112  of the bushing, with the second outer diameter OD 2  being preferably less than that of the first outer diameter OD 1 . The outer diameters are spaced apart from the inner diameters for illustrative purposes and to distinguish and clarify what dimension is referred to for each diameter; the respective inner and outer diameters should be considered as intersecting the bushing  46  at the same latitude. The outer diameters and the inner diameters are eccentric of one another, or are not centered on the same axes. More specifically, the first inner diameter ID 1  is eccentric of the first outer diameter OD 1 , and the second inner diameter ID 2  is eccentric of the second outer diameter OD 2 . However, the outer diameters OD 1  and OD 2  may be substantially coextensive along the same axes.  
         [0036]     Referring further to  FIG. 6A , the bushing  46  is shown having a first side  114  and a second side  116 . The bushing  46  normally encircles the shaft  44 , but is shown having the first side  114  and the second side  116  for illustrative purposes. Because of the eccentric diameters discussed above, the first side  114  has a first thickness T 1  and the second side  116  has a thickness T 2 . The thickness T 1  can be thicker or thinner than the thickness T 2  depending on the amount of throw desired for the crusher. The overall thickness of the bushing  46  tapers evenly from the thickness T 1  to the thickness T 2 . The tapered thickness of the bushing also contributes to the solid contact made between the shaft  44  and the bushing  46 , thereby further reducing potential burning of the bushing  46 .  
         [0037]      FIG. 6B  depicts an overhead view of the shaft  44  and the bushing  46 . As described with respect to  FIG. 6A , the overall thickness of the bushing  46  tapers evenly from the thickness T 1  to the thickness T 2 . The thicknesses T 1  and T 2  do not necessarily need to be located on the right and left sides of the shaft  44 , respectively. Since the bushing  46  is preferably circular throughout its length, it should be understood that actual orientation of the thickness T 1  and T 2  will be determined as to what angle or perspective a person is looking at the shaft  44  and the bushing  46 .  
         [0038]     The inward tapering of the bushing  46  and the tapering of the thickness do not have to be substantial to result in the desired effect for the crusher  10 . For instance, in many industrial-sized rock crusher assemblies, the shaft  44  may be about 45 inches in length. This would be the length below the rock crusher head, and not include the length of the shaft that may extend inwardly of the crusher head. The first inner diameter ID 1  may be approximately about 13⅞ inches and the second inner diameter ID 2  may be approximately about 10¼ inches. The change in the bushing diameter is around 3 to 3½ inches, or approximately 1 inch taper in thickness for every 12 to 15 inches of the length of the shaft. Similarly, the difference between the thickness T 1  and T 2  of a bushing, for a shaft of about 45 inches in length, is approximately 130 mils, or approximately 1/8 of an inch. The slight adjustments are enough to provide for a more efficient bushing. It should also be understood that the above values could be adjusted depending on specific needs or arrangements for a rock crusher. Provided that the varying of the bushing dimensions produces an even, abutting surface along the entire length of the shaft, the values would fall within the scope of the invention.  
         [0039]     The bushing  46  has been discussed as being evenly tapered. It may be possible that the outside of the bushing does not evenly taper, and the bushing would still fall within the scope of the invention. Also, either the top of the bushing or bottom of the bushing, where the bushing may not come in contact with the shaft, may not necessarily be evenly tapered either. Provided that the surface of the bushing that comes into contact with the surface of the shaft is evenly tapered so that individual pinch points between the shaft and the bushing are removed, the bushing would fall within the scope of the invention.  
         [0040]      FIGS. 7 and 8  further depict the head and shaft assembly  26 . The head  43  comprises the mantle  48 . The mantle  48  is of a generally conical design, extending outwardly from the locking nut  118  to the edge of the head  43 . The feed plate  42  is connected to the mantle with a locking nut  118 . As previously noted, the domed feed plate  40  sits upon the feed plate  42  and is connected to the feed plate  42  with connecting means  120 , such as bolts, screws, or other securing devices. Preferably, the domed feed plate  40  is removably secured to the dome feed plate  42 . The domed feed plate  40  preferably has a curved, raised middle section  122  and two relatively flat side sections  124 ,  126 . Though the shape of the side sections  124 ,  126  is not necessary for the present invention, they are arranged to facilitate installing or removing of the domed feed plate  40  when necessary, by providing easy access to the connection means  120 .  
         [0041]     The domed feed plate  40  has two primary advantages over the prior art. Rocks entering the crushing bowl  24  may be of any size or shape, including large, flat rocks, or “slabby” rocks. In prior art rock crushers, when these slabby rocks fell into the crushing bowl  24 , they would have a tendency to get caught between the bowl liner  52  and the feed plate, which decreases productivity by slowing down the progression of the rocks through the crusher and potentially interrupting the crushing process by having to remove the slabby rocks. The present design of the domed feed plate  40  prevents such slabby rocks from getting caught or trapped in the crushing bowl  24 . When the slabby rocks encounter the domed feed plate  40 , the curved shape of the dome feed plate  40  provides a surface that will disorientate the rocks from a potentially horizontal, slab position and allow the rocks to proceed through the crushing cavity more efficiently.  
         [0042]     The domed feed plate  40  also provides protection for the locking nut  118 . The cost of replacing the locking nut  118  is much more than that of the domed feed plate  40  or the feed plate  42 . Thus, the use of the domed feed plate  40  helps to reduce costs for the operation. Furthermore, the domed feed plate  40  has a more substantial size or height than the feed plate  42 . As such, it can withstand more wear and tear from the entering rocks without wearing out, resulting in replacement of the feed plate  42  less frequently than in prior art designs. The domed feed plate  40  reduces down time for replacement parts, which increases the overall yield of the crusher  10  over prior art designs.  
         [0043]     Referring further to  FIGS. 3 and 8 , the head and shaft assembly  26  further comprises a floating ring  130 . The fluid is pumped through the passageway  132  through the wiper  130  into a cavity  134  surrounding the wiper  130 . It should be understood that the system may have more than one wiper  130 , passageway  132 , or cavity  134 , and still fall within the scope of the present invention. The use of singular references is for clarity and should not be considered as limiting on the invention. A seal retainer  136  is affixed to the head  43  to form the cavity  134 . Fastening means  138 , such as screws, bolts, or similar devices, secure the seal retainer  136  and the head  43  together. Preferably, the fastening means  138  are designed and arranged to insure they will not loosen when subject to vibrations and movements associated with the rock crusher  10 . As the pumped fluid enters the cavity  134 , it forms a protective barrier for the inner moving parts of the head  43 . Dirt, dust, and debris will be prohibited from entering the cavity  134 , thereby extending the lifetime of the head  43  and the shaft  44  and all of their various internal components. When the fluid is pumped into the cavity  134 , it is possible that some of the fluid will pass outwardly into the rock discharge area and may coat some of the rocks with it. However, the amount of fluid that does discharge into the rock discharge area is a minimal amount and should not be considered as problematic, either with the crushing process or with environmental concerns.  
         [0044]     A vertical groove  133  allows oil to be provided for the shaft assembly  26  and, also, the bushing  46 . The groove  133  is preferably arranged at 90° to the load of the crusher  10 , which further increases the load capacity of the bushing  46 . The design of the groove  133  insures that the load capacity will be carried throughout the entire length of the bushing  46 , which substantially increases the load capacity compared with prior art rock crushers. Also, as shown in  FIG. 3 , a side entry port  180  delivers lubrication to the shaft assembly  26 . The side entry port  180  provides lubrication for a lower step bearing  182  and an upper step bearing  184 , among other components of the shaft assembly  26 , including the socket liner  54 . This arrangement greatly reduces any potential pressure buildup below the eccentric  45 , thereby minimizing problems associated with the eccentric  45  lifting upwards and resulting in nonalignment between the shaft  44  and the bushing  46 , further increasing the efficiency of the rock crusher  10 .  
         [0045]     The head and shaft assembly  26  are designed to minimize stress caused by the interaction of the internal parts of the assembly  26 . For instance, the shaft  44  and the head  43  are preferably connected through an interference fit, and further secured with the threaded portion  44   a  interacting with the locking nut  118 . Together, these locking means prevent the head  43  loosening from the shaft  44  due to flexing or bending of the shaft  44  under a crushing load. Also, the pivot point for the gyration of the head  43  is relatively higher compared to previous designs, which allows the mantle  48  to travel in a direct line towards the bowl liner  52  (see  FIG. 3 ). This allows rocks to be pinched and crushed directly without slippage. To further minimize stress and wear on the various liners of the crusher  10 , the head and shaft assembly  26  rotates at a very slow rate, preferably 30 RPM or less, when there is no load in the cavity  25 . Overall, the head and shaft assembly  26  is much more efficient than prior art assemblies.  
         [0046]      FIGS. 9 and 10  further depict the crusher  10  and the frame  12 . The frame  12  is designed so that the clamping cylinders or tramp cylinders  30  will act as shock absorbers for the crusher  10  when the crusher  10  encounters an un-crushable or tramp material.  FIG. 9  depicts the clamping cylinders  30  arranged around the outside of a lower section  140  of the body  16  of the frame  12 .  FIG. 10  depicts the adjustment ring assembly  72 , which sits on top of the frame  12 . The lower end  78  of the cylinder  30  is connected to a mount  144  located on the base  14  of the frame  12 . The upper end  76  of the cylinder  30  is connected to an upper mount  146  located on the adjustment ring  72 . The cylinders  30 , which are preferably a rod-type hydraulic cylinder, will allow the adjustment ring  72  to lift off the mainframe  12  when tramp material is encountered between the mantle  48  and the bowl liner  52  (see  FIG. 3 ), thereby allowing the tramp material to pass through the crushing cavity and preventing the crusher from jamming. The mount  144  and the upper mount  146  preferably comprise a simple clevis and pin design, which allows the cylinders  30  to rotate slightly when tramp material is passed through the bowl  24 , or when the tramp material is jammed within the bowl  24 . Also, the cylinders  30  are preferably mounted upside-down with respect to conventional mounting styles, which further protects the internal cylinder rods  145  and the seals  147  from dirt that accumulates during the crushing process. The added mobility and arrangement of the cylinders  30  helps to minimize wear on the cylinders  30  and improve the reliability of the cylinders.  
         [0047]     As shown in  FIG. 9 , the cylinders  30  are connected by a plurality of fluid lines  148  that allow fluid to flow through the cylinders  30 . The fluid lines  148  also connect each of the cylinders  30  to a built in relief valve  150 . The relief valves  150  maintain a predetermined pressure for the cylinders  30  and are preferably of a cartridge-type valve that may easily be replaced if necessary. When material jams up the crusher  10 , the adjustment ring  72  will lift, which in turn extends the cylinder  30 . Fluid is released from the cylinder  30  through the relief valve  150  to minimize the pressure rise, which adds an increased level of safety for the crusher  10  components when tramp material is inside of the bowl  24 . The cylinder  30  is thus provides two distinct features by providing clamping force between the adjustment ring  72  and the frame  12  and, also, provides the necessary lift of the adjustment ring  72  with respect to the frame  12  when the crusher  10  needs to be cleared of material. This is an improvement over previous tramp systems that used nitrogen accumulators to regulate the pressure for the tramp releases. The operator may run the crusher  10  at the most efficient setting to maximize the tonnage of saleable product without concern of the crusher  10  stopping or jamming, since the crusher  10  may be cleared safely and automatically within a few minutes of a jam being detected.  
         [0048]     Referring to  FIG. 10 , the adjustment ring assembly  72  is shown in further detail. The motor  80  is mounted on the upper section of the adjustment ring  72  and comprises a motor pinion  152  that interacts with an adjustment gear  154  (see also  FIGS. 1 and 3 ). The adjustment gear  154  works together with the adjustment cap  38  and the bowl  24  to rotate the bowl  24  either clockwise or anti-clockwise for changing the crusher setting as required and to assemble or disassemble the bowl  24  from crusher  10 .  
         [0049]     Referring further to  FIGS. 9 and 10 , the locking cylinders  158  interact with the locking collar  160  to provide the means for securing or locking the bowl  24  in place during crushing operation. A passageway  162  allows the hose to be connected to the locking cylinders  158  to supply the fluid pressure needed to lock the bowl  24 .  
         [0050]     The foregoing is considered as illustrative only of the principles of the invention. Furthermore, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described. While the preferred embodiment has been described, the details may be changed without departing from the invention, which is defined by the claims.