Abstract: In a hand-operated label printing machine, including a hand lever and a printing head attached to the hand lever; a printing pressure buffer mechanism or a constant pressure printing mechanism which comprises: in a first embodiment, a spring-actuated engaging member formed in the hand lever and a cooperating checking shoulder which is formed in the main body of the machine; an inclined groove leads to the shoulder; the shoulder is brought into disengageable engagement with the spring-actuated engaging member for moderating the printing pressure; and when the spring-actuated engaging member rides over the checking shoulder, the printing head is actuated; in a second embodiment, a pressure receiving engaging member is carried on the hand lever, through a lost motion connection; a pressure contact member and a guide member are both carried on the main body of the machine and are spaced apart; the pressure receiving engaging member is integrally provided with a pressure receiving piece having a cam surface at the

Abstract: A contant pressure printing mechanism for use with a hand labeler which prints a label: an actuating lever, which is pivotally connected to the frame of the hand labeler, is divided into a hand lever and a printing lever, and both of these levers are also pivotally connected. A printing head is carried by the printing lever. The hand lever and the printing lever are biased to move together as a unit. The operating lever engages a snap mechanism which applies a preset resistance to rotation of the operating lever as the printing lever is turned toward the printing platen. In one embodiment, the snap mechanism includes a pressure roller and a snap bail. The pressure roller is rotatably mounted to either the hand lever or the frame of the hand labeler while the snap bail is mounted pivotally to the other. As the squeezing of the hand lever increases, the operating lever snaps past the snap mechanism and the snap movement urges the printing lever toward the platen.

Abstract: A constant pressure printing mechanism for use in a portable label printing machine, or the like: a pressing member is attached to a hand operated driving lever which carries the printing head and which is pivotally attached to the machine frame; a separate rocking lever is pivotally attached to the machine frame; a pressure receiving member attached to the rocking lever is in position to be engaged by the pressure member as the driving lever pivots; continued pivoting of the driving lever causes subsequent separation of the pressure receiving and pressure members, thereby again freeing the rocking member from being pivoted; a platen pivotally secured to the machine frame is normally biased away from the printing head; an elastic buffer member is stretched between the rocking lever and the platen for pivoting the platen toward the printing head when the rocking member is pivoted by the pressure member; with the provision of the constant pressure printing mechanism of the invention, the intensity and the conta

Abstract: A printing pressure damping mechanism for a hand labeler: A printing platen is pivotally mounted on the frame of the hand labeler. The platen has a printing portion at one side of its center of pivotal motion. A hand lever pivotally connected to the frame of the labeler carries a printing head, which is turned toward the printing platen when the hand lever is squeezed against the biasing force of a return spring. Shock-absorbing means, comprising a leaf spring on the hand lever and an elastic abutment member on the other side of the printing platen from the printing portion engage to turn the printing portion of the printing platen toward the printing head. The hand lever is further squeezed and moves to overcome the biasing force of the leaf spring when the printing head abuts against the printing portion of the platen. The squeezing force, which might otherwise be applied as a printing force to the printing platen through the hand lever, is damped to a preset level.