US 4,541,558 AGranted

Riveting press safety

AssigneeWilliam Prym-Werke KG

InventorsErnst Herten, Eilhelm Eiringhaus

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Abstract

A riveting press wherein a stationary lower tool is in line with a vertically reciprocable upper tool which is moved up and down in response to rotation of a first cam mounted on the output shaft of an electric motor. The output shaft carries a second cam with an endless cam groove for the follower at the upper end of a first elongated bar which is coupled to the upper portion of a second elongated bar with limited freedom of reciprocatory movement. The lower portion of the second bar carries a pair of grippers which can releasably hold a component of an article of hardware to be affixed to a sheet of textile material between the two tools. A coil spring biases the two bars apart so as to increase the distance between the follower and the grippers and to thereby close an electric switch which is in circuit with the motor. If the grippers encounter an obstruction on their way toward the sheet on or adjacent to the lower tool, the switch opens because the upper bar moves downwardly relative to the lower bar and the motor is arrested. The groove of the second cam has a portion of greater width to allow for movement of the follower in such portion of the groove in the radial direction of the second cam. This enables the press to apply components of articles of hardware to thicker or thinner workpieces.

Claims17

Dependent claims

In a machine for applying components of articles of hardware or the like to sheet- or web-like workpieces, the combination of a first tool;

a second tool movable toward said first tool from a retracted position in which said tools define a space for a workpiece therebetween;
first drive means for reciprocating said second tool from and back to said retracted position;
means for releasably holding a component between the workpiece in said space and said second tool, said holding means being movable with and relative to said second tool between a first position remote from and a plurality of second positions nearer to said first tool;
and second drive means for moving said holding means between said positions, including a rotary cam defining an endless path, a first reciprocable motion transmitting member having a follower extending into said path, a second motion transmitting member connected with said holding means, means for coupling said members to each other with limited freedom of movement, means for yieldably biasing said members in directions to increase the distance between said follower and said holding means, a prime mover operable to rotate said cam, and a device for preventing the operation of said prime mover in response to movement of one of said members relative to the other of said members against the opposition of said biasing means when said holding means encounters an obstacle on its way from the first to a second position, said path having a portion which allows said follower to move radially of said cam in that angular position of the cam in which said holding means is at least close to a second position.

1 more element

Dependencies are inferred from the claim text.