Safety means for powered machinery

This invention provides a safety means for powered machinery comprising a conventional wire mesh safety glove adapted for wearing by the machine operator. The machine with which it is used has a grounded frame, an electrical motor, a control switch, with the electrical motor being connected to a source of electrical energy through the control switch. A control safety circuit connects the electroconducting wire mesh safety glove and bypasses the conventional control switch for the machine which is in turn connected to the motor of the machine. The safety circuit includes a circuit breaking means, preferably a relay, whereby the relay will open and deprive the motor from electrical power whenever the wire mesh glove comes in contact with the grounded frame of the machine. An alternate form of the invention connects the wire mesh glove of the operator to the antenna of a wireless electromagnetic transmitter worn by the operator. The circuit breaking means includes a wireless electromagnetic receiver means which remains closed when receiving a radio signal, or any wireless signal, but which will open when the antenna of the wireless electromagnetic transmitter is grounded to the frame through the wire mesh glove touching the frame which serves to interrupt the transmission of the radio signal, or any wireless signal. This causes the electrical power to the motor to be interrupted.

BACKGROUND OF THE INVENTION 
Meat skinning machines with sharp skinning knives, and gripping rolls, can 
cause severe injury to an operator whose hands come in contact with the 
knives of these machines. 
Therefore, a principal object of this invention is to provide a safety 
means for powered machinery which will automatically deprive the machine 
of power when the operator even touches the machine in even a 
non-emergency situation. 
A further object of this invention is to provide a safety means for powered 
machinery wherein the operator does not need to actuate a separate 
emergency switch to cut power to the machine. 
A still further object of this invention is to provide a safety means for 
powered machinery that is fully automatic. 
These and other objects will be apparent to those skilled in the art. 
BRIEF SUMMARY OF THE INVENTION 
This invention provides a safety means for powered machinery comprising a 
conventional wire mesh safety glove adapted for wearing by the machine 
operator. The machine with which it is used has a grounded frame, an 
electrical motor, a control switch, with the electrical motor being 
connected to a source of electrical energy through the control switch. 
A control safety circuit connects the electroconducting wire mesh safety 
glove and bypasses the conventional control switch for the machine which 
is in turn connected to the motor of the machine. The safety circuit 
includes a circuit breaking means, preferably a relay, whereby the relay 
will open and deprive the motor from electrical power whenever the wire 
mesh glove comes in contact with the grounded frame of the machine. 
An alternate form of the invention connected the wire mesh glove of the 
operator to the antenna of a wireless radio transmitter worn by the 
operator. The circuit breaking means includes a wireless radio receiver 
means which remains closed when receiving a wireless signal, but which 
will open when the antenna of the radio transmitter is grounded to the 
frame through the wire mesh glove touching the frame which serves to 
interrupt the transmission of the radio signal. This causes the electrical 
power to the motor to be interrupted.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
The numeral 10 designates a conventional meat skinning machine having a 
frame 12, an elongated sharp cutting knife 14, an electrical motor 16 
(FIG. 4) and a conventional foot switch 18. The motor 16 operates a 
gripping roll 12A which functions in conjunction with cutting knife 14 to 
sever the skin from a portion of meat. The motor 16 is connected to a 
source of electrical energy (not shown) through foot switch 18. The 
skinning machine 10, as described, is conventional in the art and does not 
of itself comprise the instant invention. 
The numeral 20 designates a conventional wire mesh glove which is worn in 
packing plants by various operators to protect the hands from knives and 
other sharp instruments used in the meat processing operations. Glove 20 
in FIG. 1 is connected by lead 22 to a control safety circuit 24. Safety 
circuit 24 is embodied in the machine 10 and is comprised of conventional 
components including transistor 26, logic gates 28 and 30, and timer 32. A 
normally closed relay 34 is connected to a source of electrical energy 
through transistor 26, and to motor 16 by leads 36 and 28. Leads 39 and 
39A extend towards switch 18 and a source of electrical pwoer. Ground wire 
40 connectr frame 12 to a suitable electrical ground. 
In operation, the operator closes foot switch 18 which causes electrical 
energy to pass towards closed relay 34 through lead 39A to motor 16. 
However, as shown in FIG. 2, when the lead 22 is connected to the ground 
wire 40 by reason of the glove 20 engaging the grounded frame 10, gates 28 
and 30 are turned on. The input power from lead 39A is thereupon blocked, 
whereupon the relay 34 is opened, (see dotted line 34A in FIG. 2) thus 
denying electrical power to the motor 16. Timer 32 serves to maintain the 
polarity of transistor 26 to keep relay 34 open for a preset period of 
1-10 seconds so that motor 16 will not instantly restart when the 
grounding of the machine is broken by removing contact of glove 20 with 
frame 12. 
As a result, the skinning machine 10 will be stopped whenever the glove 20 
comes into engagement with the machine. The machine will be stopped even 
when an emergency situation does not exist. Obviously, power to the 
machine will be stopped upon any contact between the glove and machine 
regardless of whether the glove touches the machine in a dangerous area or 
in any other area. 
An alternate form of the invention is shown in FIGS. 3 and 4. A control 
safety circuit 24A is shown in FIG. 4 and includes a radio transmitter 42 
which is preferably battery operated and which is carried on the person of 
the operator. Transmitter 42 includes an antenna 44 which is grounded to 
glove 20 by lead 46. Transmitter 42 has a conventional on and off switch 
47. 
Control safety circuit 24A includes a wireless radio receiver 48 comprising 
a relay 35 similar to the previously described relay 34. Relay 35 is 
imposed between the source of electrical energy (not shown) and motor 16 
and foot switch 18. Radio receive 48 includes a conventional antenna 50. 
While a radio transmitter, receiver and signal are disclosed herein, it is 
expected that the invention can be practiced by the use of conventional 
wireless transmitters, receivers, and signals to the extent that they may 
differ from a specific radio signal, providing they retain the wireless 
attribute of radio signals. 
In operation, the operator will turn the switch 47 of transmitter 42 to an 
on position which causes a wireless signal to be sent from antenna 44 on 
the transmitter 42 to the antenna 50 on receiver 48. This will cause relay 
35 to move to the closed position so that when foot switch 18 is closed, 
electrical power will be delivered to motor 16. 
However, whenever the glove 20 touches the grounded frame 12 of machine 10, 
the antenna 44 will be grounded, thus interrupting the transmission of the 
radio signal or any wireless signal from antenna 44 to antenna 50. This in 
turn will cause relay 34 to open, whereupon electrical energy to motor 16 
will be immediately interrupted. 
Thus, from the foregoing, it is seen that this invention will achieve at 
least all of its stated objectives.