1. An apparatus for mounting a heat seal bar on a heater unit in a machine successively making plastic bags, the apparatus comprising:
a receiving recess formed in the heat seal bar to be opposed to the heater unit;
an insert received in and fixed to the receiving recess to extend in a direction in which the receiving recess is opposed to the heater unit, the insert including external and internal end portions and a side, the insert further including an axial groove formed therein to open to the side so that an axial opening is formed in the side;
an adjacent recess formed in the heat seal bar to be disposed adjacent the receiving recess in a direction crossing the direction in which the receiving recess is opposed to the heater unit, the adjacent recess being communicated with the axial opening and the axial groove;
a tension pin supported by the heater unit to extend toward the heat seal bar and terminate at a head formed thereon, the tension pin being inserted into the adjacent recess and then inserted into the axial groove through the axial opening;
an inward protrusion formed on the insert to protrude into the axial groove at the external end portion of the insert; and
an actuator member provided at the heater unit, the tension pin being actuated by the actuator member to be pulled and moved axially thereof and relatively to the heater unit after being inserted into the axial groove so that the head is engaged with the inward protrusion, the tension pin and the insert cooperating with each other to mount the heat seal bar on the heater unit.
2. The apparatus set forth in claim 1 wherein an inner groove is formed in the heat seal bar about the receiving recess at the internal end portion of the insert, an outward protrusion being formed on the insert at the internal end portion, the outward protrusion being fitted into the inner groove so that the insert is fixed by the outward protrusion and the inner groove.
3. The apparatus as set forth in claim 1 wherein the receiving recess comprises a hole including an inner thread formed therein, the insert including an outer thread formed thereon, the insert being engaged with the hole threadedly to be fixed to the hole by the inner and outer threads.
4. The apparatus as set forth in claim 1 wherein the insert has a U-shaped section so that the axial groove comprises a semi-circular portion and a straight portion, the inward protrusion protruding into the semi-circular portion and the straight portion, the semi-circular portion having a center, the inward protrusion including a tapered surface formed thereon about the center of the semi-circular portion, the head having a circular-shaped section to include a tapered surface formed thereon, the tapered surfaces being engaged with each other to position the heat seal bar when the head is engaged with the inward protrusion.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
What is claimed is:
1. A tube element, for example, for braces, railings on scaffolding, support structures and similar tube constructions, in which at least at one end of the tube ends there is constructed a hook for the releasable fastening of the tube element on a different structural part, wherein a holding part of the hook is inserted into the tube end of the tube element, wherein the tube end and the holding part are pressed together, wherein the hook consists of two plates which are spaced from one another, and between which a safety bolt provided with a hook eyelet is pivotably fastened, wherein the safety bolt has a locking element facing toward an axis, and wherein the safety bolt has on its edge face at least one shoulder laterally offset with respect to the axis, which shoulder projects beyond the plates of the hook.
2. The tube element according to claim 1, wherein the face of the safety bolt has two shoulders lying on both sides of the axis.
3. The tube element according to claim 1, wherein the nose is shaped such that it projects in the closed position beyond the contour of the hook.
4. The tube element according to claim 1, wherein the safety bolt has on the side opposite the nose a bearing surface, which in the open position of the safety bolt extends into the space of the hook eyelet.
5. The tube element according to claim 1, wherein the locking element has a stepped locking surface.
6. The tube element according to claim 1, wherein the shoulder extending toward the tube element has a nose supported on the hook andor the tube element.
7. The tube element according to claim 1, wherein the hook is punched out of a flat material, of which two parts are placed against one another, and wherein holes andor face-side notches are provided in the holding part, into which holes andor notches is pressed the material of the tube element.
8. The tube element, for example, for braces, railings on scaffolding, support structures and similar tube constructions, in which on at least one end of the tube ends there is constructed a hook for the releasable fastening of the tube element on a different structural part, wherein the tube end is lined with a tube sleeve, the cross section of which is chosen in such a manner that the outer contour of the tube sleeve is approximately equal to the inner contour of the tube end, whereby the length of the tube sleeve exceeds the one of the hook, and wherein the hook is constructed on a holding web from end pieces of the tube end and of the tube sleeve, which end pieces are upset together flat in the area of the hook, so that a hook eyelet is removed from the holding web.
9. The tube element according to claim 8, wherein the flat upset end pieces form a holding web which is symmetrical with respect to the longitudinal axis of the tube element.
10. The tube element according to claim 8, wherein the flat upset end pieces are spaced from one another.
11. The tube element according to claim 10, wherein a flat safety bolt is pivotal about a hook axis between the end pieces, which hook axis is arranged in the tube end and is positioned perpendicular to the longitudinal axis of the tube element.
12. The tube element according to claim 8, beads or similar indentations are deepened into the surfaces of the flat upset end pieces of the tube end, which beads or indentations extend into the surfaces of the adjacent, flat upset end pieces of the tube sleeves.
13. The tube element according to claim 9, wherein the free end face of the tube end and the outer face of the tube sleeve are flush with one another.
14. The tube element according to claim 8, wherein the height of the recess of the hook eyelet is greater than its width, and wherein the height of the knob is greater than the width of the recess.
15. The tube element according to claim 14, wherein the width of the recess of the hook eyelet becomes smaller toward its opening.