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PLATE TWO
THE INTERLOCKING MECHANISM

The two diagramatic views shown on this chart illustrate the operation of the interlocking mechanism, and give a general picture of the different parts or sections, as well as the relation of each part to the others. The interlocking mechanism provides a control over the other operating mechanisms on the torpedo tube, and is a guard against improper operation of the tube, preventing accidental or unintentional firing. Each related part of the interlocking mechanism must be in its proper position before the other mechanisms can be set in operation.

These two diagrams and the descriptive matter herewith should be studied in connection with Chapter 4, which describes and illustrates the interlocking mechanisms and their operation more comprehensively.

The functions of the different parts of the interlocking mechanism may be described, briefly, as follows:

1. The threads on the muzzle door operating shaft (J) give the cylinder slide (E), which operates in the breech bracket, a forward and backward motion when the shaft is rotated to open or close the muzzle door. Therefore, in order to open the muzzle door, the breech and muzzle door interlock handle (O) must be in the "Muzzle Door Unlocked" position. This removes the breech and muzzle doors interlock bolt (Q) from the slot in the cylinder slide (E), and places it in front of the shoulder or lug on the breech door locking ring (K), thereby locking the breech door closed.

The drain valve interlock lever (L) must also be-in "Drain Valve Locked" position, which removes the drain valve interlock head (F) from the slot in the cylinder slide (E), and places the interlock bolt (U) in front of the latch (T) on the drain valve interlocking shaft. The drain valve must be fully closed in order to do this.

The cylinder slide (E) is now free to move on the muzzle door operating shaft (J), so the muzzle door may be opened.

With the muzzle door opened, the cylinder slide (E) prevents the breech door from being unlocked and opened, and also prevents the drain valve from being opened.

2. With the cylinder slide (E) in "Muzzle Door Opened" position, as shown in the upper diagram, the shoulder on the firing interlock bolt (H) is free to rotate down when the firing interlock lever (F) is moved to the "Tube Ready to Fire" position.

If the muzzle door is closed, the shoulder on the firing interlock bolt (H) is prevented from rotating own, and the firing interlock lever (F) can not be moved to the "Tube Ready to Fire" position.

When the firing interlock lever (F) is in "Tube Ready to Fire" position, the shoulder on the bolt (H) prevents any motion of the cylinder slide (E), and the muzzle door can not be closed.

3. To place the firing interlock lever (F) in the "Tube Ready to Fire" position, the impulse stop valve must be open so that the interlock bolt (B) on the impulse stop valve stem (A) is removed from the path of the shutter bar (C), as shown in the upper diagram.

4. With the firing interlock lever (F) in "Tube Ready to Fire" position, as shown in the upper diagram, the shutter bar (C) prevents the closing of the impulse stop valve, and the hole in the shutter bar (C) is lined up with the piston rod (D). This allows the piston rod (D) to pass through the hole, the shutter bar and open the pilot valve, thereby venting the upper part of the firing valve and firing the tube.

If an attempt is made to fire the tube when the shutter bar (C) is not in the correct position, the piston rod (D) lodges in a recess in the shutter bar (C), this recess being sufficiently deep to prevent any motion of the shutter bar until the air pressure has been released from the torpedo stop cylinder, thereby allowing the stop piston to return to its original position. This eliminates the possibility of attempting to fire the tube with the shutter bar out of position, and then moving the shutter bar to the correct position and allowing the piston rod to go through the hole and open the pilot valve.

When the spindles on the depth setting mechanism (M) and the speed setting mechanism (N) are all in the "Spindle Out" position, as shown in the upper diagram, the interlock sleeve (G) is free to rotate, and the firing interlock lever (F) may be moved to the "Tube Ready to Fire" position.

To engage these spindles in their respective slots in the torpedo, the firing interlock lever (F) must be in the "Muzzle Door Unlocked" position, as shown in the lower diagram. This rotates the interlock sleeve (G), and brings the slot in the bar of the depth setting interlock (M) into position so the depth setting lever may be moved to the "Spindle In" position.

The shoulder on the interlock sleeve (G) will rotate out of the way of the bar on the speed setting lever (N), and the lever may be moved to the "Spindle In" position.

NOTE

The two diagramatic view's on this chart show the interlocking mechanisms as they apply to torpedo tubes having manually operated muzzle door mechanisms. The interlocking mechanisms which are applicable to torpedo tubes equipped with power operated muzzle door mechanisms are shown on Plate Three.


Torpedo tube interlock ready to fire.

A Impulse stop valve stem Valve locked, open
B Impulse stop valve interlock bolt
C Shutter bar
D Piston rod of Firing Mechanism Torpedo Stop cylinder
E Slide in muzzle door open position,
F Firing interlock lever in Tube Ready to Fire Position
G Interlock sleeve
H Firing interlock bolt
J Muzzle door operating shaft
K Breech door locking ring
L Drain-valve interlock lever in Drain Valve Locked Position
M Depth setting mechanism Spindle Locked Out
N Speed setting mechanism Spindle Locked Out
O Breech and Muzzle Door interlock Handle in Breech Door Locked Position
P Drain valve interlock head
Q Breech and Muzzle Door Interlock Bolt Disengaged from slide and engaging lug on locking ring
R Rod extending down to drain valve interlock bolt
S Lever connecting drain valve interlock rod and Drain valve Interlock Bolt
T Latch on drain valve operating shaft, Drain valve Locked closed
U Drain valve interlock bolt
V Drain valve operating lever

Torpedo tube interlock ready for loading.

A Impulse stop valve stem Valve Closed
B Impulse stop valve interlock bolt
C Shutter bar
D Piston rod of Firing Mechanism Torpedo stop cylinder
E Slide in Muzzle door closed position
F Firing interlock lever in Muzzle Door Unlocked Position
G Interlock Sleeve
H Firing Interlock Bolt.
J Muzzle Door Operating Shaft
K Breech Door Locking Ring
L Drain valve interlock lever in Muzzle Door Closed Position
M Depth Setting Mechanism Spindle Unlocked
N Speed Setting Mechanism Spindle Unlocked
O Breech and Muzzle Door Interlock Handle in Breech Door Unlocked Position
P Drain valve interlock head Engaging Slot in Slide
Q Breech and Muzzle Door Interlock Bolt Engaging slide and releasing lug on Locking Ring
R Rod extending down to drain valve interlock bolt
S Lever connecting drain valve interlock rod and drain valve interlock bolt
T Latch on drain valve operating shaft, Drain valve open
U Drain valve interlock bolt
V Drain valve operating lever

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Version 1.10, 22 Oct 04