US551601A

US551601A - And boston

Info

Publication number: US551601A
Authority: US
Publication date: 1895-12-17
Anticipated expiration: 1912-12-17

Description

(No Model.)

. A. W. PEARSALL. VALVE-FOR PNEUMATIC DESPATGH TUBE SYSTEMS.

, No. 551,601. Patentd Dec. 17, 1895.

2o pointed out in .the claims.

' UNITED STAT S ATENT F 3 ALBERT W. PEARSALL, OF NEWV YORK, N. Y., ASSIGNOR TO THE METEOR DESPATOH COMPANY, OF PORTLAND, MAINE, AND BOSTON, MASSACHU- SETTS.

VALVE FOR PNEUMATIIQ-DIISPATCH-TUBE SYSTEMS.

srncrrrcnrron forming'part of Letters Patent No. 551,601, dated December 17, 1895.

Application filed October 15, 1894.

To aZZ whom itmay concern:

Be it known that I, ALBERT W; PEARSALL,

of New York, county of New York, and State of New York, have invented new and useful 5 Improvements in Valves for Pneumatic-Dispatch-Tube' Systems and I hereby declare that the following is afull, clear, and exact description of the invention, which will enable others skilled in-the art to which it apro pertains to make and use the same.

My invention relates to certain newand useful improvements in vacuum-valves for terminals in pneumatic e dispatchtube systerms in which the carriers are propelled by I 5 suction-i. 6., by withdrawing thepressure from the front of'the carrier as it travels through the system; and it consists of certain novel features, arrangements, and combinations hereinafter described, and particularly In the drawings, Figure 1 represents a perspectiveview of the terminal at the salesmans station. Figl 2 is a side view of the interior of the terminal with one of the sides A removed. a 7 7 In the drawings like letters of reference re for to like parts.

The terminal A, which is known in the art as an upward discha'rge terminal and can be used at either the cashiers or the salesmens stations, consists of an outer curved guidingwall A andflat sides A and with flat bottom A so that it presents to the view a'box of an oval form curved on top and with a flat bot- 3 5 tom. There is provided on the inside of this box a curved guiding-wall A which may be cast or otherwise secured to the sides A of the box, or it maybe 'cast or otherwise secured to the bottom WallA of the terminal, 40 and it extends around in the arc of a circle and terminates a short distance above the bottom wall 'of the terminal, and with the outer curved wall A it forms between them for the carriers a passage A which is a continuation of the inlet-tube B, through which the carriers are sent'to the terminal, and it is secured to the bottom. wall'A of the terminal between the outer wall A and'the inner wall A so that the carrier on entering the termi 5o nal passes up between the side walls and Serial No. 525,877 (No model.)

around the passage A forming a continuation of the tube B, to the valve 0 at the bottom of the terminal, which is opened by the impact of the carrier as it passes from the inlet-tube B around the passage A to said valve, and the air-current passes under the lower end of the wall A into the return suction-tube D, through which the carriers are returned, and this keeps up a continuous aircurrent in the system.

a The valve '0 consists of two leaves 0 and O mounted fast on the shaft 0 whichis journaled in the lower sides of the terminal. Below the leaf Otthere is located a movable slide 0 by which the area of the bottom of 6 3 the leaf O exposed to the atmospheric pressure can be increased or decreased, as desired. The other leaf, C ,'of'the valve fits closely in the bottom wall of the terminal and is' exposed on its upper surface to the suction of the system and on its lower surfacelto the atmospherio pressure, and with this leaf 0 the carrier drawn through the system impacts and opens the valve and permits its discharge from the terminal. The carrier A coming through the passage A opens said valve by its impact with the leaf 0?, and the valve assumes the position shown indotted lines, Fig.

2, as the'carrier is delivered from the terminal, with the leaf C raised up and contacting with the inner side of the inner wall A and thus closing the air-passage under the wall A between the passage A and the return suction-tube D, which is secured to the bottom wall of the terminal.

As soon as the carrier passes from the terminal and past the leaf C the air-current between the passage A and the suction-tube D on the top side of the leaf 0* forces said leaf back to its normal position and thus closes the terminal to the atmosphere, and the air-current continuesthrough the tube B, terminal A and return suction-tube D.

' A preferable construction of the terminal consists in casting the same in 'two upright 5 parts, which are firmly held together by bolts E, passing through and secured in the side walls A Supposing this terminal is located at the salesmans'station and it is desired to return the carrier to the salesman from whom' it was sent, it is placed in the branch tube 1*, connected with the return-tube D, and said branch tube F is covered by a self-closing clapper F, hinged at W, and at this point provided with a projection F which limits the upward throw fof the clapper, and on its opposite side with a projection F by which the clapper is raised by the hand to permit the insertion of the carrier, and after the carrier has been pushed in the clapper is drawn to its seat and held closed by the suction in the system.

As will be seen from the drawings, the bottom wall A fits under a part of the bottom of the leaf 0* and thus reduces the area of the bottom surface of that leaf exposed to atmospheric pressure, and under the center part of the leaf 0 there moves a slide 0 on the tongue 0, and closely fitting against the bottom of the said leaf to prevent access of air to that part of the bottom surface of the leaf with which the slideis in contact, so that the extent of area of the leaf C exposed to atmospheric pressure can be regulated.

As the area of the bottom of the leaf 0" exposed to atmospheric pressure is less than the area of the bottom of the leaf C exposed to the said atmospheric pressure, the difference in amount of pressure on the bottom of the two leaves of the valve will hold the said valve 0 suflieiently tight against the sides of the terminal, thus preventing any leakage, and at the same time make it easy for the carrier to operate the leaf C of the valve. If none of the bottom surfaces of the leaf 0* were exposed to atmospheric pressure it would be diflicult for the carriers to open the valve by their impact with the top of the leaf C, but the provision by which the atmospheric pressure is admitted to a less area on the bottom of the leaf 0 than on the bottom of the leaf C not only holds the valve closed to its seat but at the same time permits the easy operation of the valve by the impact of the carrier on the top of the leaf C It is obvious that if the above arrangement were not provided to produce a difference of area of the bottom of the leaves exposed to atmospheric pressure and the area exposed to atmospheric pressure on both leaves was the same there would be produced an exact balance which would not hold the valve closed to its seat and which would swing more or less in the opening in which it was pivoted.

The main object, therefore, of my invention is to provide an arrangement by which the area, exposed to atmospheric pressure, of the bottom surface of the leaf of the valve with which the carrier impacts is greater than the area exposed to atmospheric pressure of the bottom of the opposite leaf.

By the provision of the movable slide G the area of the bottom of the leaf 0* exposed to atmospheric pressure may be increased to overcome the increased pressure on the delivery side of the valve, due to the increased friction of a long line thereby enabling the carrier dispatched on a long line to be deli vered as easily as one dispatched on a short line.

Of course it will be understood that the construction shown simply illustrates one manner of carrying out my invention, as it is obvious that other constructions could be adopted which would embody the main principle of my invention.

I do not limit myself to the exact arrange ment and construction shown, as the same may be varied without departing from the spirit of my invention.

Having thus ascertained the nature and set forth the construction of my invention, what I claim as new, and desire to secure by Letters Patent, is-

1. In a pneumatic dispatch tube system, the combination with a terminal having an. opening for the discharge of carriers, of a valve consisting of two leaves and normally closing said opening,and adapted to be opened by the impact of the carriers with one of said leaves, the atmospheric pressure on said leaf with which the carrier impacts tending to hold the valve closed, and the atmospheric pressure on the other leaf tending to open the valve.

2. In a pneumatic dispatch tube system, the combination with a terminal having an opening for the discharge of carriers, of a valve consisting of two leaves having different areas of surface exposed to atmospheric pressure and normally closing said opening and adapted to be opened by the impact of the carriers with the lea-f having the greater area of surface exposed to atmospheric pressure, the atmospheric pressure on the leaf with which the carriers impact tending to hold the valve closed, and the atmospheric pressure on the other leaf tending to open the valve.

In a pneumatic dispatch tube system, the combination with a terminal having an opening for the discharge of carriers, of a valve consisting of two leaves and normally closing said opening and adapted to be opened by the impact of the carriers with one of said leaves, the atmospheric pressure on the leaf with which the carriers impact tending to hold the valve closed, and the atmospheric pressure on the other leaf tending to open the valve, and means for varying'the area of exposed surface of the latter leaf.

4:. In a pneumatic dispatch tube system, the combination with a terminal having an opening for the discharge of carriers, of a valve consisting of two leaves having different areas of surface exposed to'atl'nospheric pressure and normally closing said opening and adapted to be opened by the impact of the carriers with the leaf having the greater area of surface exposed to atmospheric pressure, the atmospheric pressure on. the leaf with which; the carriers impact tending to two subscribing Witnesses, on this 3d day of hold the Valve closed, and the atmospheric October, 1894. pressure on the other leaf tending to open the valve, and means for varying the area of eX- ALBERT PEARSALL' 5 posed surface of the latter leaf. Witnesses:

In testimony whereof I have signed my A, S, TEMPLE,

name to this specification, in the presence of S. H. TROW.