26 - S. BENT RUSSELL 



while the discharge through 32 tends similarly to move meter 

 disc 34 to the left. These discs are mounted on meter stem 38 

 which moves in guides 36 and 37. In figure 3 the meter stem 

 is shown in mid position as it would be if the discharges from 

 30 and 31 were equal. Should the stream from pipe 30 become 

 greater than the other the discs would take a position more 

 to the left. 



The position of the meter discs determines the position of 

 slide valve 43 through the meter link 39, the rocking lever 40, 

 the connecting rod 41 and the slide valve rod 42. The slide 

 valve should be balanced so as to reduce friction. When it 

 moves to the right it opens admission port M2 to pressure from 

 pipe 51 through chamber 44 and it opens port Mi to exhaust 

 passage 50 through 44 thus causing the piston 46 to move to 

 the right. The slide valve ports, piston, etc., are of familiar 

 construction. ■ 



The combination of discs, cones, etc., forms the stream meter. 

 It will be seen that the stream meter controls the hydraulic 

 cylinder. But the stream meter is controlled in turn by the 

 transmitters that govern the tributary streams. If the sum of 

 the streams from transmitters S2n, S4n, S6n, and S8n, be greater 

 than the sum of the streams from transmitters Sin, S3n, S5n, 

 and Syn, the piston rod 47 will move out. If it be less, the 

 piston rod will move in. Now, the stream from a single trans- 

 mitter is variable as has been shown, so that the stream from 

 S2n alone may be greater than the added streams from Sin 

 and S3n. From this it may be seen that if the transmitters 

 Sin, S3n, and S2n are opened simultaneously, the movement of 

 the piston rod may be either outward or inward according to 

 the frequency with which S2n has previously been operated. 



By the system above described we see that we have a hydraulic 

 cylinder that is subject to the control of any one of its trans- 

 mitters and also to a variety of combinations of transmitters 

 working in concert, the result in each case depending largely 

 upon what might be called the "experience" of the transmitters 

 in the combination. 



The system described is for use with hydraulic pressure or 

 compressed air. An equally practical system which will not 

 here be described is for use with electric control, i.e., with elec- 



