Installation of sequential loading of bars of material in a machining center

An installation for sequential loading of bars of material, referred to as bars, in a spindle of a machine for machining these bar, the installation comprising an elongated element, referred to as pusher, which:

• has an end, referred to as front end, which is intended to exert an action on one of the opposite ends of a bar, referred to as first end, in order to be able to ensure the translatory movement of this bar,
• is placed under the control of a device referred to as first device and capable of ensuring the translatory movement of this pusher in two opposite directions, referred to as first direction and second directions, in such a way as to move the front end, in the first direction, towards the interior of the machine or, in the second directions, towards the interior of the installation and be able
• in the first direction, bring this front end into contact with the first end of a bar, aligned beforehand with the pusher and ensure a contact with this first end, so that at the latest after the bar has been engaged by another end, referred to as second end, through the entrance of a passage that the machine has in the alignment of its spindle and up into a component of the spindle, referred to as spindle nose, and at the level of which said bar can be held tightly with a view to allowing the machining of a portion which exceeds this spindle nose,
• also in the first directions, to move sequentially the front end in such a way as to move the bar by a fraction of its length, in particular so that the products can be successively machined then taken from this bar,
• in the second direction, to extract from the machine the front end of the pusher in a manner so as to allow, afterwards, a new movement of the front end in the first direction towards a first end of a new bar, preloaded, i.e. aligned beforehand on this front end with a view to a new cycle of operations of loading and of movement of a bar,
• the pusher comprising at least one first part which has the front end and a second part that is connected to the first device and these two parts, referred to together as sliding parts, are mounted sliding one in the other in such a way as to be mobile, one with respect to the other, along an axis referred to as sliding axis, and this between two states which are
• a first state which, referred to as state of contraction, corresponds to a state in which one of said sliding parts is retracted in the other, conferring to the pusher a usable length for moving the front end between the entrance of the passage aligned on the spindle and the spindle nose, which is of minimal size, and
• a second state which, referred to as state of extension, corresponds to a state in which one of said sliding parts extends partially outside the other, and this over a distance of extension the value of which is predetermined, conferring to the pusher a usable length of a maximal value,
• this installation, wherein:
• the sliding parts are placed under the control of a control device, referred to as second device, which makes it possible to influence the transition of the pusher from its state of contraction to its state of extensions, and, reciprocally,
• the first device and the second device are placed under the control of a control device, referred to as third device, which allows at least at the start of one of the two operations which are, on the one hand, the operation of loading of the bar into the machine and, on the other hand, and operation of movement of the bar in said machine by a value, referred to as first value, necessary to achieve a product, taking into account the effective length of this bar during the operation under consideration and of verification by calculation of whether the usable length of the pusher under consideration in state of contraction is sufficient to ensure at least one of the two operations consisting of
• moving the bar to bring its second end s substantially up into the spindle nose, and
• moving the bar by a fraction of its length which corresponds to the value necessary to achieve a product, and
• if the usable length of the pusher in state of contraction is of a sufficient value, then maintaining such a state of contraction and, on the contrary, if the usable length is insufficient, then activating the relative translation of the sliding parts of the pusher (to obtain the state of extensions of this pusher.