US1731176A

US1731176A - Safety guard for band saws

Info

Publication number: US1731176A
Application number: US250562A
Authority: US
Inventors: Ross Emmett William
Original assignee: Individual
Current assignee: Individual
Priority date: 1928-01-30
Filing date: 1928-01-30
Publication date: 1929-10-08
Anticipated expiration: 1946-10-08

Description

. 1929. E. w. R058 SAFETY GUARD FOR BAND SAWS 2 Sheets-Sheet Filed Jan. 30. 1928 E. w. R085 1,731,176

SAFETY GUARD FOR BAND SAWS Filed Jan. 50, 1928 2 Sheets-Sheet 2 5 .M 1% 1/1 J 1 2 W 2 F/ 2 m 7% v m, w wfl j H M #4 H 0 w \y \\\y g \x J 29 1/, Km A///%%%////// Oct. 8, 1929.

Patented 02:11. 8, 1929 rrso STATES EMMETT WILLIAM ROSS, OF CAMDEN, NEW JERSEY SAFETY GUARD FOR BAND SAWS Application filed January 30, 1928. Serial No. 250,562.

The object of my invention is to provide a guard for a band saw which is so arranged that, when the guard is lowered, the driving mechanism will be automatically stopped, and

when the guard is raised and held in its raised position, the electric contact will be made so that a motor that drives the sawwill be placed in circuit.

The invention also relates to certain details which will be fully described hereinafter.

In the accompanying drawing:

Figure 1 is a face View of the upper portion of the band saw;

Fig. 2 is an enlarged view of the guard,

the slide'way being in section to show the contacts Fig. 3 is an edge view;

Fig. 4 is a sectional plan view on the line 44 of Fig. 2;

Fig. 5 is a view similar to Fig. 2, with the guard raised and contacts made; and

Fig. 6 is a diagram of the wiring used in the present instance.

Referring to the drawings, 1 is a band saw which passes around an upper wheel 2 and a lower driving wheel which is not shown in the drawings. This wheel,'in the present instance, is driven by an electric motor, shown at a, Fig. 6, and the driving connection may be made in any manner desired.

In the present instance, the saw is adapted to a guide 3 which is carried by the frame 4 which supports the bearing for the stud 5 on which the wheel 2 is mounted. 6 is a table through which the saw blade extends, and at the rear of this table is a guard 7 for the return run of the saw. 8 is a wire screen which is located in front of the upper wheel and acts to protect the operator from coming in contact with said wheel.

In order to protect the operator at the working side of the saw, I secure a slide-way 9 to the guide 3, and in a groovein this slide-way is located a slide 10 having at its lower end r a handle 11, by which it can be raised. On the slide is a keeper 12 beveled at its upper face and this keeper is arranged to engage a spring latch 13 secured to the slide-way. The latch holds the slide 10 in its raised position, but when the latch is withdrawn from the the table or onto the work located on the table.

011 the slide is a stop 14 made in any suitable manner, which is arranged to come in contact with a crossbar 15 at the upper end of the slide-way. This stop limits the upward movement of the slide.

On the slide is a contact plate 16 and on the slide-way are three

terminals

17, 17 and 17", these contacts being connected to

wires

18, 18 and 18 respectively, as shown in diagrain in Fig. .6. These wires are enclosed in a cable 19.

20, 20 and 20 are wires leading to and from the motor w, and 21, 21 and 21 are wires which are arranged to be connected to the

wires

20, 20 and 20 by a series of

switches

22, 22 and 22 The Wire 18 is connected with the wire 21; the wire 18 is connected to the wire 20; and the wire 18 is connected to a coil 23 which, in turn, is connected to the wire 21 as shown in the diagram.

When the guard 10 is in the position shown in Fig. 1, then the contact plate is clear of the

terminals

17, 17 and 17 but, when the operator raises the guard, the contact plate 16 comes in contact with the terminal 17", then with the terminal 17, and, finally, when it ,has reached its full height, with the terminal 17 the plate in the meantime having passed the terininal li so that when the terminals '17? and 17 are in contact with the plate, the

coil 23 is energized. This coil is connected to the

switches

22, 22 and 22" and throws the switches into the active position in con tact with the terminals of the

wires

21, 21 and 21 lVhen the guard 10 is raised to'its full height, then the terminal 17" is cut out and the terminal 17 comes in contact with the plate, the circuit being completed through the

wires

18 and 20, motor a, wires 21, coil 23, and wire 18*. This is the ordinary wiring generally used in motor-driven machinery.

To release the guard 10, the latch 13 is drawn, allowing the guard 10 to drop onto the table in front of the'saw, the contact plate passing the terminals and out of contact with said terminals when in its guarding position.

While I have illustrated one particular arrangement of wiring, it will be understood that the wiring may be modified without departing from the essential feature of my invention, which is to so construct the guard that when the guard is lowered the mechanism for driving the saw will be stopped, and when the guard is raised the saw will be set in motion.

I claim:

1. The combination in a band saw, of a table; a frame; a slideway mounted on the frame; a sliding guard adapted to the slideway and arranged to drop in front of the saw between the slideway and the table; a motor for driving the saw; and switching mechanism which will cut out the motor and stop the saw when the guard is lowered and will start the motor and the saw when the guard I is raised.

2. The combination in a band saw, of an electric motor for driving the saw; a table; a fixed slideway above the table; a guard adapted to slide in said slideway and located in front of the saw so that when it is lowered it will guard the active run of the saw between the table and the slideway; a contact plate on'the slide; a terminal in the slideway connected with the motor, said terminal being in contact with the plate on the slide when the guard is raised. and being out of contact when the guard is lowered, breaking the circuit and stopping the motor.

3. The combination in a band saw, of a frame; a table; a saw; a guide located above the table in front of the saw; a slide arranged to be raised and lowered so as to guard the active portion of the saw; a contact plate on the guard; and a series of spaced terminals on the slideway, said plate on the guard being clear of the terminals when the guide is lowered, stopping the motor and consequently the saw, and when the guard is raised the plate will be in contact with the terminals and the motor will be set in motion.

4. The combination in a band saw, of an electric motor for driving said saw; a table; a frame above the table; a slideway mounted on the frame; a sliding guard adapted to the slideway; electric terminals exposed in the slideway; and a plate on the slide in contact with the terminals when the slide is raised and held in its raised position, and when the slide is released it will drop onto the table or the Work thereon and will form a guard for the saw and the plate will be clear of the terminals, stopping the motor and the saw.

EMMETT WILLIAM ROSS.