Patent Application
20190168477
This disclosure relates to a method and apparatus for moving dies into and removing dies from a press with an overhead crane.
Dies are set in a press but must be removed and replaced to service the dies and change over from one die set to another. Dies are placed on a bolster plate that may include a motor drive that is used to move the die into and out of the press. Dies may also be moved with an overhead crane.
The orientation of the press and the direction that the die is moved into and out of the press is normally fixed in one reciprocal sliding direction. As shown in
This disclosure is directed to solving the above problems and other problems as summarized below.
According to one aspect of this disclosure, an apparatus is disclosed for removing and replacing a die in a press with an overhead crane. The apparatus includes an overhead crane movable in a first direction. A hoist assembly is mounted on the crane to be movable perpendicular to the first direction. The hoist assembly includes a drum rotated about an axis of rotation parallel to the first direction. A press includes a die that is movable into and out of the press reciprocally and perpendicular to the first direction.
According to other alternative aspects of this disclosure as it relates to the apparatus, the overhead crane is positioned in the first direction to center the hoist relative to an indicator at the center of the press. A load cell may be operatively connected between the drum and a hook attached to a wire rope to measure the load applied when the die is moved into and out of the press. A guard oriented parallel to and spaced from the crane girder may be attached to a crane girder to restrict the angle of a wire rope relative to the hoist assembly. A sensor system may be disposed in a sheave pocket defined by the hoist assembly for limiting the swing of a wire rope hanging from the hoist apparatus.
According to another aspect of this disclosure, a method is disclosed for setting a die in a press. The method includes the steps of positioning an overhead crane to be centered relative to a front opening in a press and securing a sling to the die. The die is then pulled with the sling attached to a wire rope wound on a drum disposed above the press. The wire rope pulls the die in a direction perpendicular to the axis of rotation of the drum.
According to other aspects of the method, the die may be removed from the press by pulling the die onto a skid adjacent to the front opening. The die may be inserted into the press by pulling the die off of the skid and into the press with the sling extending through a back opening in the press located on the opposite side of the press from the front opening.
The method may also include measuring the load applied to the wire rope with a sensor operatively attached between the wire rope and the drum, and limiting the load to a predetermined level. In addition, the swing angle of the wire rope relative to the drum may be monitored with a sensor system to limit the swing angle of the wire rope to a predetermined degree.
The above aspects of this disclosure and other aspects will be described below with reference to the attached drawings.
The illustrated embodiments are disclosed with reference to the drawings. However, it is to be understood that the disclosed embodiments are intended to be merely examples that may be embodied in various and alternative forms. The figures are not necessarily to scale and some features may be exaggerated or minimized to show details of particular components. The specific structural and functional details disclosed are not to be interpreted as limiting, but as a representative basis for teaching one skilled in the art how to practice the disclosed concepts.
Referring to
The hoist assembly 40 includes a trolley 42 that includes wheels 44. The trolley 42 moves on the wheels 44 to change the position of the hoist assembly 40 relative to the girders 36.
The hoist assembly 40 includes a drum 36 that is provided with a helical groove 48. A wire rope 50 is wound on the drum 46 in the helical groove 48. A hook 42 is connected to the wire rope 50 and a sling 54 is connected to the hoist assembly 40 by the hook 42. The sling 54 is rigged to a die 56 that is installed in a press 58. The die 56 is pulled from the press 58 by the sling 54. The die 56, when in the press 58, is attached to a bolster 60. When the die 56 is removed from the press 58, the die slides onto a skid 62 that is located adjacent to the bolster 60. The die 58 is removed from the press 58, through a front die opening 64. The die 56 is set in the press 58 by pulling the die 56 with the sling 54 being routed through a rear die opening 66 to the die 56 on the skid 62. A press cable guard 68 is provided above the front die opening 64 and also above the rear die opening 66. The press cable guard 68 protects the press 58 from the sling 54.
A press centerline indicator 70 is provided on the press 58 and a wire rope 50 and hook 52 are positioned in line with the press centerline indicator by moving hoist assembly 40 with the trolley 42. The hoist assembly 40 should be centered relative to the press 58 to remove or set the die 56 in the press 58. A girder guard 72 is provided on the girder 36 to positively limit the angle of the wire rope relative to the vertical. The girder guard 72 is located to limit the angle of the wire rope 50 relative to vertical to less than 25 degrees. The design angle relative vertical is 20 degrees. The girder guard 72 also protects the girder from being contacted by the wire rope 50. A sensor may be provided on the girder guard 70 or inside a sheave pocket 78.
A load cell 76 is shown in
The drum has an axis of rotation that is parallel to the direction B as shown in
Operation of the improved overhead crane 30 is described with reference to
Referring to
The embodiments described above are specific examples that do not describe all possible forms of the disclosure. The features of the illustrated embodiments may be combined to form further embodiments of the disclosed concepts. The words used in the specification are words of description rather than limitation. The scope of the following claims is broader than the specifically disclosed embodiments and also includes modifications of the illustrated embodiments.
