Turret punch press machine

#1. Field of the Invention

#The present invention relates to a turret punch press machine having a pair of turrets on which plural dies are mounted, and more particularly, to a turret punch press machine capable of preventing the paired turrets from being shifted from each other when their frames are deformed.

#2. Prior Art

#The present invention will become apparent from the following detailed description made about some embodiments with reference to the accompanying drawings.

#FIG. 1 is a front view showing the conventional press machine provided with the C-shaped frame;

#FIG. 2 is a front view showing the conventional press machine provided with the gate-shaped frame;

#FIGS. 3 through 5 show a first example of the turret punch press machine according to the present invention. The press machine has a C-shaped frame. Numeral 50 represents the frame which is made by welding die steels and which is installed on the floor by means of brackets 52. The frame is provided with a base frame portion 54, from one end of which a first column portion 56 extends upward. A first upper frame portion 58 horizontally extends from the upper end of the first column portion 56. A second column portion 76 extends upward from the other end of the base frame portion 54. A second upper frame portion 74 is horizontally extended from the upper end of the second column portion 76. The first upper frame portion 58 and the second upper frame portion 74 oppose, face to face, a clearance interposed between their front ends.

#The press machine is provided with a pair of upper and lower disc-like turrets 60 and 62, which have plural upper and lower die halves 64 and 66 attached to their circumferential rim portion, respectively. The upper turret 60 is rotatably attached to the front end portion of the second upper frame portion 74 by means of a shaft 82 and a bearing 78. The lower turret 62 is also rotatably attached to the base frame portion 54 by means of a shaft 84 and a bearing 80. Sprockets 86 and 88 are attached to the shafts 82 and 84, respectively, and connected to the well-known rotation drive mechanisms (not shown) by means of chains 90 and 92. Shot pin mechanisms 68 and 70 are arranged in the second column portion 76, thereby defining the rotating position of the turrets.

#A hammer 94 and a hammer driving mechanism 96 are attached to the front end portion of the first upper frame portion 58. For driving the hammer, a conventional mechanism such as, for example, a mechanism for converting rotation of a drive shaft to a reciprocating movement for hammer 94 via a crank and crank arm, or a mechanism for reciprocating the hammer 94 by oil pressure, or the like, may be used. A hammer holder 72 is arranged on the base frame portion 54, opposing to the hammer 94.