US2004161A - Dispensing valve - Google Patents

Description

June 11, 1935.

c A. FAUSEL DISPENSING VALVE Filed Feb. 7, 1933 2 Sheets-Sheet l I W m i A ,4 m Lifl 04 n 1 R N Wm M w w m 5 m mw J B 1 H I 0/ KT 2 ATTORNEY Patented June 11, 1935 UNITED STATES 4 PATENT OFFICE" magi??? mm Application February 7, 1933, Serial No. 655,609 5 Claims. (Cl. 107-29) The present invention relates to dispensing valves and has for an object to provide means for dispensing measured quantities of material from a supply.

Another object of the invention is to provide a measured quantity of a fluid and then positively discharging the same.

- Another object is to provide a dispensing valve of the character described above in which the time interval between the intake and discharge will be reduced to a minimum.

Other objects and advantages of my invention will appear in the following description of a preferred-embodiment of my invention and thereafter the novelty and scope of the invention will be pointed out in the claims.

In theaccompanying drawings;

Figure 1 is a view in vertical section of my improved dispensing mechanism, the section being taken substantially on the irregular line l-l of Fig. 2 is a view of the same in horizontal section taken substantially on the irregular line 2 2 of Fig. 1;

Fi 3- is a view of the same in front elevation with the right hand portion thereof shown in section;

Figs. 4 to 11 are views in horizontal section showing successive positions of the valve mechanism; and

' uncover the discharge port.

Fig. 12 is a diagram showing-velocity curves traced by certain piston elements of the valve.

In generalmy invention, as illustrated, comprises a pair of pistons operating in a valve cylin-- der formed with an intake port and a discharge port. These pistons are driven by a simple crank motion, the stroke of one being greater than that of the other and also out of phase therewith. As a result of this arrangement the pistons sepmate to draw in a charge of fluldwhile they cover the discharge port and open theintake port andthen they approach each other to expel the charge while they cover However; during the brief intervals when both ports are closed the two pistons have substantially the same velocity so that the spacing is maintained at a constant maximum during the transfer from intake to discharge and the spacing is maintained substantially at zero value during the return from discharge to intake.

My invention is particularly adapted for (113-.

.IS and I] the intake port and pensing measured quantities of batter in a cake baking machine such as described in application Serial No. 644,736 filed November 28, 1932, and in the accompanying drawings I have illustrated the valve in connection with a part of such a 5 machine. It will be understood, however, that' the invention is not'limited to this use, and may be employed with other machines and apparatus. In Figs. 1 to 3 a portion of the frame of a. cakebaking machine is indicated at I 0. From this frame projects a pair of studs ll adapted to fit into sockets formed in a valve body I2. Seated upon and secured to the valve body in any suitable manner is abatter reservoir l3. The valve body i2 is formed with a central bore in which is fitted a bushing M. This bushing constitutes a valve cylinder. An outlet port 15 of the reservoir communicates with an intake port I6 which opens'through the top of the valvebody and the bushing. Diametrically opposite the intake port but displaced axially of the cylinder toward the left, as viewed in Fig. 1, is a discharge port I1 which leads outwardly through the bushing and valve body.

Fitted to reciprocate in the bushing is a piston 20 comprising a sleeve 2! closed by a transverse outer end wall. Intake and outlet ports 22 and 23 are formed in the sleeve just within said wall. These ports are adapted to communicate with the ports respectively and in alternation as the sleeve is reciprocated. A second piston or plunger 25 is fitted to reciprocate in the sleeve 2| so asto draw in fluid from the reservoir during the period that the port I6 is uncovered by the port 22 and to force out the fluid after, the port 16 is closed and the port I1 is uncovered by the port 23.

Reciprocation of the two pistons is effected by crank mechanism which will now be described. Suitably journaled in the frame l0 isa vertical shaft 26 and carried upon this shaft is a wheel 21'; Projecting from'the upper face of the wheel is a stud 28 which is fitted into a, socket 29 eccen'trically located in the wheel. The stud is fixed by any suitable means against turning in the socket.

. The direction of rotation of the wheel 21 is m v cheatedby the arrow in Fig. 2. It will be observed its free end. Pivthat the pin is spaced radially further from the center of the wheel than is the stud 28, and also that the stud 28 is angularly advanced with respect to the pivot pin 35 so that as the wheel 21 is rotated the two pistons will reciprocate isochronously but asynchronously and the stroke of the piston 25 will be greater than that of the piston 20.

To permit of stopping operation of the valve without stopping the shaft 26, a clutch is provided. This may be of any s table type. adapted to stop the wheel in a. predetermined position when the clutch is released. The particular clutch illustrated in Figs. 1 and 2 comprises a collar fixed to the shaft 26 and. formed with a peripheral notch 4|. Pivoted on the wheel 21 is a clutch lever having a hooked end 42 adapted to engage and catch in the notch and being normally urged into engaging position by a spring 43. The other end of the clutch lever carries a pin 44. The hooked end. 42 is thrown out of engagement with the notch 4! by a control arm which may be moved to clutch releasing position, as shown in full lines in Fig. 2. This arm has a beveled end, which, when'the arm is in releasing position, lies in the path of the stud 44, wedging the stud inward and therebyswinging the hook 42 outward to clear the notch 4|. A stop pin 45 takes the thrust of the arm 45 while it is wedging the clutch lever clear of the notch. When the arm 45 is in l the idle position indicated by broken lines in Fig. 2 the clutch will remain in engagement and the valve will continue to operate.

When the control arm is set to releasing position the wheel will continue to turn and the valve will continue to function until it has completed its dispensing cycle, whereupon the beveled end of the control arm 45 will force the clutch lever clear of the notch 4|. To assist in withdrawing the hook 42 and to insure arrest of the wheel 27 as soon as the hook is withdrawn, the wheel is formed with a peripheral flange 48 having a notch 49 therein. A pivoted arm 55 carries a roller 5! which rides on the periphery of the flange, being urged into engagement therewith by a spring 52. Whenever the wheel 21 reaches the predetermined clutch releasing position the roller 5i drops into the notch 49 giving the wheel a slight forward thrust and freeing the hook 42 so that it may readily be withdrawn should the arm 45 be in releasing position. Engagement of the roller 5i with the notch will also check further rotation of the wheel 21. To reengage the clutch the control arm 45 is swung to its idle position, pennitting the spring 43 to force the hook 42 into engagement with the clutch collar 40 so that it will drop into the notch 4! as soon as the latter comes around. It will be observed that the leading wall of the notch 49 is relatively steep so as to give the de sired forward thrust to the wheel while the trailing wall is sloped to wedge the roller 5i outward with little effort when the clutch is engaged.

The operation of the dispensing valve may now be followed by referring more particularly to Figs. 4 to 11. It will be observed that the pistons reciprocate with a substantially harmonic motion.

. Fig. 4 shows the parts just after a charge has been dispensed. Both ports 15 and i! are closed and'both pistons are moving inward or toward the right, as shown in said figure. The axis of link 32 is substantially at 'right angles to the radius of the wheel 21 passing through the stud 28. Consequentlm'the piston 20 is moving at its maximum velocity which at the moment is substantially equal to the velocity of the piston 25. .The

end face of the latter piston is in contact with as the port 22 begins to uncover the port IS, the piston 25 will begin to pull away from the piston 2i] and a space will begin to form between the pistons. As the space expands batter will be sucked therein from the reservoir l3.

Fig. 5 shows the piston 25 at the instant when its velocity is at a maximum, while the piston 20, although still moving inward or toward the right is decelerating rapidly.

In Fig. 6 the piston 20 has substantially reached the limit of its inward motion, while piston25 although decelerating is still moving away from piston 20 and the space between the pistons is still expanding.

In Fig. 7 the piston 25 has substantially reached the limit of its inward stroke while the piston 26 is moving outward so that the space between pietons is still expanding butis nearing its maximum.

Fig. 8 shows the two pistons just after the maximum separation thereof has been effected. In this position the two pistons are moving in the same direction and at about the same rate so that there is substantially no change in volume of the space between the pistons and this constant maximum volume is maintained during the transfer period after the port 66 has been cut off completely and up to the point at which the port i1 begins to open. As soon as the latter port begins to open the two pistons commence to approach each other forcing the charge out of the discharge port I'l.

Fig. 9 shows piston 2i) at the end of its outward stroke while the piston 25 is rapidly catching up to it and expelling the charge of fluid.

In Fig. 10 the piston '25 is starting back but is being overtaken by the piston 20. Just before the port I! is closed by the piston 2d the two piston faces will have come into contact reducing the spacing to zero and then during the return transfer interval, when the port II is entirely closed, up to the time that the port I5 begins toopen, the twt pistons will move at substantially the same velocity. Fig. 11 shows the pistons at the beginning of this return transfer interval.

Thus, from the moment that the intake port it begins to open and up to the moment that it is entirely closed the space between the pistons is expanding and the rate of expansion increases as the port 66 is being uncovered and decreases as said port is being closed. Similarly the space between pistons contracts throughout the period thatthe port I1 is open and the rate of contraction increases as the port is being uncovered and decreases as the port it is being closed. During each of the brief transfer intervals when both of said ports are closed there is substantially no variation in the velocity of the two pistons. It will be noted, however, that during the transfer periods the pistons are moving at approximately their highest velocity so that the time intervals between intake and discharge are reduced, to a minimum.

Aclearer understanding of the relative movement of the pistons maybe obtained from the diagram Fig. 12, which shows velocity curves of the two pistons respectively. In this diagram,

time is measured along the axis of abscissa: and

E-F-G. It will be observed that these curves are out of phase and that the curve EF'G is of a greater amplitude than the curve A-B-C but the two curves are of equal time periods. It will also be observed that between the points H and I the two curves are substantially coincident while in the time period J to K the two curves are most widely separated and yet are substantially parallel. The period H-I represents the transfer interval when the two pistons are mov-' ing inward from the instant when the port I1 is closed to the instant when the port l6 begins to open, while the interval JK represents the transfer period when the pistons are moving outward from the time when the port I6 is entirely closed to the instant when the port I! begins to open. Obviously, the curves are at no point mathematically parallel but the parallelism is very close during the transfer intervals H--I and J-K when the transfer is being made between the'closing of one port and the opening of the other.

It will be understood that the particular embodiment described above is to be taken as illustrative and not limitative of my invention. For instance, it will be observed that the axis of the pistons does not pass diametrically through the center of the wheel 21 but obviously the parts can be so disposed as to provide this diametric relation, or, if desired for purposes of convenience in the design of the machine to which the valve is applied, the offset of the axis of the piston might be greater than that illustrated; In any case the parts can be so designed as to secure substantial coincidence and parallelism of the velocity curves during the be set according to the desired volume of charge that is to be dispensed.

Having thus described my invention what I claim as new and desire to secure by Letters Patent is as follows:

I claim:

1. A dispensing valve comprising a casing formed with an intake port and adischarge port, a pair of pistons reciprocable in said casing to open and close said ports in alternation, the ports lying in planes spaced apart lengthwise of the casing to provide an idle transfer interval after each port is closed before the next port is opened,

and mechanism for continuously driving the pistons in mutually timed relation such that the pistons will draw apart only when the intake port is open and will draw together only when the discharge port is open, the relative positions of the pistons remaining substantially constant during said transfer intervals with the pistons substantially in mutual contact during the transfer interval immediately following the closing of'the discharge port.

2. A dispensing valve comprising a casing formed with an intake port and a discharge port, a pair of pistons reciprocable in said casing and adapted to open and close said ports in alternation, the ports lying in planes sufficiently spaced apart lengthwise of the casing to provide an idle transfer interval after each port is closed before the other port is open, and means for reciprocating said pistons with isochronous but asynchron ous strokes and with a greater amplitude of movement of one piston than of the other whereby the pistons will draw apart only while the inports in alternation, the

two transfer intervals respectively, and the maximum separation may take port is open and will draw together while the outlet port is open, the relative positions of the pistons remaining substantially constant during said transfer intervals with the pistons substantially in mutual contact during the transfer interval immediately following each closing of the discharge port.

3. A dispensing valve comprising a casing formed with an intake port and a discharge port, a piston reciprocable in the casing to open said ports being suiiiciently spaced apart lengthwise of the casing to provide an idle transfer interval after each port is closed before the other port is open, a second piston also reciprocable in the casing, and a crank drive for each piston, one crank drive having a greater throw than the other and being angularly displaced with respect to the other whereby the pistons will draw apart while the intake port is open and will draw together while the discharge port is open but will travel at substantially equal velocity during each of said transfer intervals, the pistons being also so related that they will be substantially in mutual contact during the transfer interval immediately following each closing of the discharge port.

4. A dispensing valve comprising a casing formed with an intake port and a discharge port, a piston reciprocable in the casing and having a sleeve extension providing a chamber and formed with openings'therethrough adapted to communicate respectively with the intake and discharge ports, the ports lying in difierent transverse planes so that they will alternately establish communication with said chamber, said planes being sufllciently separated to provide an idle transfer period in each piston stroke when both ports will be closed, a plunger reciprocable in the chamber to vary the volume thereof between a predetermined maximum and substantially zero, and means for driving the piston and the plunger continuously in relatively timed relationso as to expand the chamber only while it is in communication with the intake port and contract the same only while it is in communication with the discharge port while maintaining the chamber at substantially constant volume during each transfer period. a

5. A dispensing valve comprising a casing formed with an intake port and a discharge port, a piston reciprocable in the casing and having a sleeve extension providing a chamber therein and formed with openings therethrough adapted to communicate respectively with the intake and discharge ports, the ports .being sufllciently spaced apart lengthwise of the casing so that they will be opened alternately to said chamber with an idle transfer period in each stroke of the piston when both ports will be closed, a plunger reciprocable in the chamber to vary the volume thereof, a double throw crank providing two pivot bearings at different. central axis of the crank and with one bearing angular-1y advanced with respect to the other, and links connecting the piston and the plunger to said bearings respectively, whereby the chamber will expand while it is in communication with the intakeport and will contract while it is in communication with the discharge port but will be maintained at constant volume during each transfer-period.

CHARLES A. FAUSEL.

radial distances from the

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