Machine tool holder with automatic hook-up

The present invention relates to a system for attaching a tool holder to a machine tool which includes an automatic hook-up of an electrical, pneumatic or hydraulic connector to supply power to the tool holder. The system includes an attaching sleeve slidably mounted on the tool holder mounting stud. A spring interposed between the mounting stud and the attaching sleeve exerts a biasing force on the attaching sleeve. The power connector is separable and has a portion attached to the machine tool and a mating portion movably attached to the tool holder. A pin interconnects the attaching sleeve and the movable mating portion of the connector.

BACKGROUND OF THE INVENTION 
The present invention relates to a machine tool holder, which may be 
associated with a machine tool turret, having an automatic power hook-up 
with the machine tool. 
When setting up a tool holder on a machine tool, it is frequently necessary 
to hook-up a device mounted on the tool holder to a connector mounted on 
the machine tool which may supply electrical, pneumatic or hydraulic power 
to the tool holder. The connection between the machine tool and the tool 
holder transmits electrical, pneumatic or hydraulic power to the tool so 
that various tool functions may be carried out. Generally, these hook-ups 
require separate operations manually carried out by the machine tool 
operator, thereby lengthening the set up time and introducing the 
possibility of incomplete or incorrect hook-up resulting in improper 
operation of the tool. 
A known tool holder mounting is illustrated in FIGS. 1 and 2. As 
illustrated, the machine tool 1 defines an opening into which is inserted 
the mounting stud for the tool holder 2. A gripping slider 3 is movably 
attached to the machine tool 1 such that, when in the position shown in 
FIG. 1, it is expanded so as to facilitate the insertion of the mounting 
stud of the tool holder 2. 
As illustrated in FIG. 2, movement of the gripping slider 3 in the 
direction of arrow 4 causes the angled surfaces 5 and 6 to slide against 
one another, thereby urging the flange 8 into contact with the surface 9 
of flange 7 formed on the mounting stud. Further movement of the gripping 
slider 3 pulls the stud and the tool holder 2 towards the machine tool 1 
in the direction of arrow 4 until teeth 10 on the tool holder 2 are in 
engagement with the teeth 11 formed on the machine tool 1. This engagement 
locks the tool holder 2 into its proper position on the machine tool 1. 
SUMMARY OF THE INVENTION 
The present invention relates to a system for attaching a tool holder to a 
machine tool which includes an automatic hook-up of an electrical, 
pneumatic or hydraulic connector to supply power to the tool holder. The 
system includes an attaching sleeve slidably mounted on the tool holder 
mounting stud. A spring interposed between the mounting stud and the 
attaching sleeve exerts a biasing force on the attaching sleeve. The power 
connector is separable and has a portion attached to the machine tool and 
a mating portion movably attached to the tool holder. A pin interconnects 
the attaching sleeve and the movable mating portion of the connector. 
When the mounting stud of the tool holder is inserted into an opening 
defined in the machine tool, the attaching sleeve also extends into the 
opening. A flange formed on the attaching sleeve is engaged by the 
gripping slider of the machine tool. Movement of the gripping slider urges 
the attaching sleeve and the tool holder against the machine tool until 
teeth formed on the tool holder and the machine tool are in mutual 
engagement. The spring force acting between the tool holder mounting stud 
and the attaching sleeve is such that the tool holder and attaching sleeve 
move as a unit until the teeth are in mutual engagement. 
Further movement of the gripping slider causes relative movement between 
the attaching sleeve and the mounting stud. This movement of the attaching 
sleeve moves the movable mating connector portion into engagement with the 
opposite connector portion on the machine tool. 
The system according to the invention provides an automatic hook-up between 
the tool holder and the machine tool that is easily operable, safe and 
reliable. The system is particularly applicable to multiple-connector 
pickups used in automated machining systems.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
The system according to the invention, as illustrated in FIGS. 3 and 4, 
comprises a machine tool 1 having a slidable gripper sleeve 3 movable with 
respect to the machine tool 1 in the direction of arrow 4. The actuation 
of the gripper slider 3 is achieved by any means known in the art and the 
operation of this gripper slider is the same as that previously described 
and illustrated in FIGS. 1 and 2. Movement of the gripper slider 3 in the 
direction of arrow 4 causes sliding between the angled surfaces 5 and 6 so 
as to urge flange 8 into contact with surface 22 flange 21 formed on 
attaching sleeve 19. 
Attaching sleeve 19 is slidably mounted about mounting stud 20a integrally 
attached to the tool holder 20. A compression coil spring 23 operatively 
interposed between the mounting stud 20a and the attaching sleeve 19 
exerts a biasing force on the attaching sleeve 19 urging it downwardly as 
illustrated in FIG. 3. 
Machine tool has a portion 12 of a separable connector attached thereto. 
The mating portion 24 of the connector is movably attached to the tool 
holder 20. Connector portion 24 may have connector elements 25 extending 
therefrom which engage the connector portion 12. Movable mating connector 
portion 24 is connected to the attaching sleeve 19 via pin 26. Quite 
obviously, the relative positions of the connector elements may be 
reversed without exceeding the scope of this invention. 
In operation, the mounting stud 20a and the attaching sleeve 19 are 
inserted into the machine tool 1 when the gripping slider 3 is in the 
position shown in FIG. 1. Movement of the gripping slider 3 in the 
direction of arrow 4 causes engagement of the flange 8 with the surface 22 
formed on the flange 21 to thereby pull the tool holder 20 towards the 
machine tool 1. The biasing force exerted on the attaching sleeve 19 is 
such that the attaching sleeve 19 and the tool holder 20 move toward the 
machine tool 1 as a unit with no relative movement between them. 
Such movement continues until the teeth 32 formed on the tool holder 20 are 
in engagement with the teeth 33 formed on the machine tool 1. As 
illustrated in FIG. 3, the position of the mating connector portion 24 is 
such that it is out of mating engagement with the connector portion 12 
located on the machine tool 1. 
Since, at this point, further movement of the tool holder 20 in the 
direction of arrow 4 is prohibited by its contact with the machine tool 
further movement of gripping slider 3 causes attaching sleeve 19 to move 
with respect to the attaching stud 20a, overcoming the biasing force 
exerted thereon by spring 23. Such further movement of the attaching 
sleeve 19 also causes movement of the mating connector portion 24 due to 
the interconnection of these elements by pin 26. Movement of mating 
portion 24 brings the connector prongs 25 into mating engagement with the 
connector portion 12 located on the machine tool 1. 
Stop means are provided to limit the relative movement of the attaching 
sleeve 19 and the mounting stud 20a so as to prevent damage to the 
connector prongs 25. The stop means may comprise a flange 28 attached to a 
lower portion 27 of the attaching sleeve 19 which interacts with a flange 
30 formed on stop member 31 fixedly attached to the tool holder 20. As can 
been seen in FIG. 4, the flange 28 contacts a surface 29 of the flange 30 
to limit the upward movement of the attaching sleeve 19. 
Although a separable electrical connector has been illustrated, it is to be 
understood that any separable connector such as a pneumatic or hydraulic 
connector, may be utilized with this system without exceeding the scope of 
this invention. 
The foregoing description is provided for illustrative purposes only and 
should not be construed as in any way limiting this invention, the scope 
of which is defined solely by the appended claims.