US3640311A

US3640311A - Circulating valves

Info

Publication number: US3640311A
Application number: US31916A
Authority: US
Inventors: Rudibert Gotzenberger
Original assignee: Individual
Current assignee: Individual
Priority date: 1970-04-27
Filing date: 1970-04-27
Publication date: 1972-02-08
Anticipated expiration: 1989-02-08

Abstract

A valve for controlling the circulation of condensate in which two telescopically disposed shells are interposed between the inlet and the outlet of the valve, one of said shells being movable in axial direction relative to the valve body, the other being rotatable about its axis, the sidewalls of the shells having ports for the throughflow of the condensate, the opening of said ports being controlled by said axial and said rotational movement of said shells.

Description

llited States Patent 1151 3,60,31 l Gotzenberger Feb. 8, 197 2 [54] CIRCULATING VALVES [56] References Cited [72] Inventor: Rudibert Gotzenberger, Fellbach, Ger- UNITED STATES PATENTS man y 2,100,494 11/1937 Sparks 062/224 1 Asslgneer Ernst Flllsch, Fellbach, Germany 3,299,829 1/1967 Jackson et al ..91/375 x Banner X [21] Appl. No.: 31,916 FOREIGN PATENTS OR APPLICATIONS 780,191 7/1957 Great Britain l37/637.4 Relmd Apphcam Data 315,577 4/1937 France ..91/375 [63] Continuation-impart of Ser. No. 712,457, Mar. 12,

1968, abandoned. Primary Examiner-Robert G. Nilson Attorney-Nolte & Nolte [30] Foreign Application Priority Data Mar. 15,1967 Germany ..F 51817 [57] ABS CT A valve for controlling the circulation of condensate in which [52] U.S. Cl ..l37/637.4, 137/599, 137/613, two telescopically disposed shells are interposed between the 62/224 inlet and the outlet of the valve, one of said shells being mova- [51] llnt. Cl ..Fl6k 31/ 145 ble in axial direction relative to the valve body, the other being [58] Field of Search ..137/625.17, 637.4; 62/224; rotatable about its axis, the sidewalls of the shells having ports 91/375 for the throughflow of the condensate, the opening of said ports being controlled by said axial and said rotational move ment of said shells.

7 Claims, 3 Drawing Figures 1 A I I v" l/y 5 7 I a 4/ I I b 32 21 20 \l 28* l 22 PATENIEU FEB 8 I172 SHEET 1 OF 2 Fig. 1

INVKNTOK RUDIBERT (XTIZENBBRGER WA rz-v /ML 7.!

PATENTEDFEB we 3640.311

MEI 2 0f 2 ,drmmm CIRCULATING VALVES This is a continuation-in-part of application Ser. No. 712,457, filed Mar. 12, 1968, now abandoned.

This invention relates to temperature-controlled expansion valves for refrigerants and the like and having inlet and outlet openings for entry and exit of the condensate (e.g., condensed refrigerant) and being equipped with two telescopically disposed cylindrical shells whose surfaces are in contact with each other, the shells being provided with openings to permit the condensate to enter the inner space of the inner shell, and with ports in their sidewalls to permit the escape of the condensate from said inner space into the valve outlet. A temperature-responsive membrane is provided to actuate axial displacement of one of the shells relative to the other whereby the relative location of the escape ports in the walls of the shells is changed.

This type of valve may be used to control the exact quantity of refrigerant to be supplied to the evaporator of a cooling installation such as illustrated in U.S. Pat. No. 2,100,494.

The flow of the refrigerant should be controlled in such a way that the refrigerant will fill the evaporator without overflowing.

One of the regulating factors controlling the flow is the evaporating temperature which, transformed into pressure, is fed into the expansion valve.

Known expansion valves of this type cannot be used for a variety of outputs of a cooling installation without additional provisions for correction of the operation; specifically it is necessary to provide the membrane with a special additional spring when energy due to superheating is applied to the membrane. The proper setting of this spring according to varying condition of operation is usually very difficult and can be performed by specially trained personnel only. Furthermore, it has to be kept in mind that the vapor pressure of the refrigerant in relation to its temperature is not represented by a linear curve. Consequently, for changing of the force of the spring applied to the membrane for control of the valve, the superheating temperatures remain constant only within a very narrow range of evaporating temperatures.

The principal object of the invention is to avoid and to overcome the disadvantages of known expansion valves of the type described.

This is achieved by providing two cylindrical shells, one having a smaller diameter and being fitted telescopically into the larger shell, the outside wall of the smaller one being in sliding contact with the inside wall of the larger one, both of these shells being disposed inside of the body of the valve. The two shells are movable relative to each other in two ways, namely in axial direction and by revolving one of the shells about its axis. The relative displacement of the two shells either by an axial movement of one of the shells or by revolving of one of the shells or a combination of these two movements will influence the relative position of the ports in the sidewalls of the shells which in turn will influence the size of the openings in the sidewalls of the two shells.

Thus, the quantity of refrigerant flowing to the outlet of the valve can be controlled not only by the axial displacement of one of the shells but also by revolving of one of the shells and thus the control of the flow of the refrigerant can easier be achieved with much greater accuracy for any operational condition of the installation.

in a preferred embodiment the outer shell is revolvable about its axis, but remains axially immovable with respect to the valve body. This arrangement simplifies the attachment of control means for the revolving movement which could be provided in form of a pair of meshing gears of which one would be fixed to and concentric with the outer wall of the outer shell whereas the other would be connected to a handwheel disposed on the outside of the valve body.

The handwheel may be equipped with indicating devices to show the angular displacement of the shell or the size of the opening or thermal output of the installation. The degree of accuracy of the control can be determined by selecting of the proper gear ratio.

For further improvement of the operation of the valve closing means may be provided to completely eliminate any flow through the valve. This is advisable for the following reasons:

To permit relative movement between the telescopically disposed shells, the fit of the two adjacent walls must not be too tight and consequently small quantities of refrigerant under pressure may escape from the inside of the inner shell even if the relative position of the two shells is such that there is no open escape port in the sidewalls of the shells.

To eliminate this disadvantage, the valve according to the invention may be provided with a closing means to completely close the flow of the refrigerant into the shells.

Such a closing means may consist basically of a hollow piston disposed inside the valve body and being coaxial with the shells and axially movable in the direction towards the opening of the shells. One outer surface of said piston is arranged to close the opening of one of the shells when said piston is axially moved towards the shells. Opposite to the closing surface, i.e., on the inside of the piston, is a space defined by the piston walls, the space being connected to the inlet by a capillary tube. Another tube coaxially disposed inside the piston and inside the inner shell connects the space inside the piston with the outlet for the refrigerant. A spring is also provided within the piston biasing the piston in the closing direction.

When the cooling installation is in operation, the refrigerant circulates through the valve. The comparatively high pressure of the condensate entering through the valve inlet acts on the closing surface of the piston and is opposed only by the reduced pressure of the condensate flowing through the capillary opening and acting, together with the spring, against the opposite, i.e., the inner side of the closing surface.

If operation of the installation is stopped, the action of the membrane will close the ports in the walls of the shells by inducing an axial movement of the inner shell, and will close the opening of the coaxial tube by actuating a closure thereof. Consequently, there will be no flow of the condensate either through the capillary tube or through the coaxial tube. No pressure is lost through the capillary tube and the pressure on both sides of the capillary tube becomes equalized. Therefore, the pressure of the spring acting in the closing direction of the piston will be the only determining factor for the movement of the piston. Thus, upon shutting down of the installation, the piston is moved automatically in the closed position and any throughflow of the refrigerant is completely eliminated. A packing may be provided between the piston and the coaxial tube.

With the inner shell being axially displaceable, the piston may advantageously be disposed between the membrane and the shells and the inlet end of the shells may be located close to the piston. It is also advantageous to firmly connect the coaxial tube with the inner shell for transmitting of the movement of the membrane thereto. The closure for the outlet end of the coaxial tube is attached to a rod passing through the coaxial tube.

The membrane itself does not have to be connected rigidly with the coaxial tube and the rod. The coaxial tube and the rod or the inner shell and the closure may, however, be equipped with springs acting in the closing direction.

A pusher pin connected at least indirectly with the membrane is provided to transmit the axial movement of the membrane to the coaxial tube and to the rod.

For immediate movement of the piston from its closed to its open position upon start of the operation of the installation, the axially movable shell and the closure for the outlet opening of the coaxial tube should be movable for closing operation in the same direction, and the axially movable shell should be provided with a stop which would prevent further movement of the shell after all ports have been completely covered. Thus upon start of the operation the closure of the coaxial tube will open the outlet opening, fluid will stream through the capillary tube and due to drop of pressure in the capillary tube the pressure exerted on the closing surface of unlvn the piston will overcome the pressure acting against the opposite side of the piston as well as the pressure of the spring.

A specific embodiment of the present invention will now be described with reference to the accompanying drawings, in which:

FIG. 1 is a sectional side elevation of the valve;

FIG. 2 is a cross section through the two shells along line 2-2 of FIG. 1; and

FIG. 3 shows diagrammatically an indicator for the control knob ofthe valve.

The valve represented in FIG. 1 and FIG. 2 comprises a valve body 1 having an inlet portion 2 and an outlet portion 3 for entry and exit of the condensate. A duct 4 connects the outlet and a space 6 beneath membrane washer 5. A membrane washer spring 7 is disposed between membrane washer and the valve body 1. A cover 50 is fastened by means of threads onto the valve housing and is provided with a dome 50a with the interior of which a capillary tube 51 communicates. The capillary tube 51 communicates at its other end in the manner illustrated in US. Pat. No. 2,100,494 with a temperature sensor at the outlet end of the evaporator (not shown) of a refrigeration system. Two

coaxial shells

9 and 10 are disposed in a sleeve 8. Shell 10, having a smaller diameter than shell 9, is disposed at least partly within shell 9. Inlet openings 13 leading into the inner space 14 of shell 10 are located in the upper end wall thereof close to inlet openings 12 to facilitate entry of condensate coming from the inlet 2.

Both

shells

9 and 10 have ports 15 disposed in the sidewalls thereof for permitting the flow of the condensate from the inner space 14 into the annular space 16 and through that space and through the outlet opening 17 into the outlet of the valve and therethrough into the evaporator.

The outer shell 9 is revolvable about its axis for adjustment of its port openings by angular displacement thereof as can best be seen in FIG. 2.

A set of meshing gears consisting of a toothed wheel 18 and toothed wheel 22 is used in connection with a control knob or control wheel 20 and spindle 21 for controlling of the revolving movement of the outer shell 9 and thereby the angular displacement of the ports.

An indicator of the type as shown in FIG. 3 may be attached to or connected with the knob 20 to indicate the angular displacement of the ports or the degree of opening thereof.

A set screw 24 riding in groove 25 in shell 9 prevents axial displacement of the shell 9 without interfering with the revolving movement thereof.

The inner shell 10 is movable in axial direction only; the axial movement being transferred to the inner shell 10 by the tube 27 coaxially disposed therewith and firmly connected thereto.

A piston 28 being disposed coaxially with the

shells

9 and 10 are located in a part 36 of the valve body for axial movement therein has an end portion 29 which serves as a closure for the upper end of the shell 9 when the piston is moved in the direction towards the shell. A capillary opening 30 is provided in the piston wall to permit a limited flow of the condensate with reduced pressure into the inner space 32 of the piston. From there the condensate flows through ports 33 into the tube 27 and through that tube into the outlet of the valve.

The tube 27 and rod 35, located inside of the tube 27 and being coaxial therewith, extend in an axial direction through the piston 28 and through the

shells

9 and 10. At the outlet end rod 35 is equipped with a stopper 37 which is designed to close the outlet opening of tube 27. The other end of the rod 35 is equipped with a flange 40 which extends beyond the tube 27. When the cooling installation reaches a low temperature the medium of comparatively lower pressure will reach the membrane space 6 through the duct 4; the membrane and with it the membrane washer 5 will be deflected downward and with it setscrew 41 will also move downwards. In consequence of this movement, a pusher 43 is pressed against the flange 40, moving the flange 40 together with rod 35 and closure 37 against the biasing force of a spring 44, whereby closure 37 opens the bottom opening of tube 27. When clamp 40 has been lowered to the upper end of tube 27, this tube begins to be lowered, against the biasing force of the spring 46, while the rod and stopper continue to be lowered; the bottom opening of tube 27 remains open during this movement. Thus a small portion of the condensate, which flows into the valve, can escape through the capillary opening 30 into the inner space of the piston 28 and from there through ports 33 and through tube 27 into the outlet of the valve. The pressure of the condensate is obviously reduced by passing through the capillary opening 30, in consequence of which the pressure in the inner space of the piston 28 is lower than the pressure of the condensate against the end portion 29 of the piston and thus the piston is kept in its upper position during the operation of the valve. If, however, the installation, of which the valve is a part, is out of operation, the membrane and with it the membrane washer will move upwards in consequence of which closure 37 and inner shell 10 will also move upwards thereby closing the bottom opening of tube 27 and the ports 15 of the inner shell 10. No condensate can escape and thus pressure will build up in the inner space of piston 28 until this pressure equals the pressure acting on the end portion 29 of the piston. The pressure of spring 45 will operate to move the piston downward whereby the end portion 29 will abut against the rim of outer shell 9 so that no condensate can escape through any space which might exist between the inner wall of shell 9 and the outer wall of shell 10. The reciprocal movements of inner shell 10 of rod 35 and of closure 37 thus control the movement of piston 28.

The piston 28 which serves mainly for quick opening and closing during the starting and the stopping operation of the installation and which may be considered to be a snap piston is biased by spring 45.

The operation of a membrane, which in turn induces the movement of the membrane washer and of parts connected therewith, is well known in the art. The membrane in a valve of the type as used for controlling the circulation of condensate reacts to changes of pressure of a respective control fluid acting thereon, the pressure being in a certain relation to the temperature and thus the membrane reacts indirectly to the temperature changes. The changing pressure of the control fluid, acting on the outside surface of the membrane in a direction which is opposite to the direction of the pressure of the condensate in membrane space 6 against the membrane washer 5, controls the movement of the membrane and with it the movement of the membrane washer and of parts connected therewith.

The valve body consists of two portions revolvable relative to each other about their axes, namely an upper portion la containing the spindle 21 for the control knob 20 and a lower portion lb containing the outlet ofthe valve.

By revolving the two portions la and 1b relative to each other, the connection between the membrane space 6 and the outlet 3 via connecting duct 4 is interrupted and the membrane space may thus selectively be connected to the outlet 19 communicating with the suction end of the refrigerant conduit adjacent the outlet end of the evaporator (not shown).

While the invention has been described by means of a specific embodiment, I do not wish to be limited thereto, for obvious modifications will occur to those skilled in the art without departing from the spirit of the invention.

What is claimed is:

l. A valve for control of circulation of a condensate, comprising:

membrane means actuable by pressure in response to temperature changes,

an elongated valve body coaxial with the membrane means and having an inlet and an outlet for the condensate,

an outer tubular shell and an inner tubular shell disposed in said valve body and coaxial therewith, said inner shell being telescopically disposed within the outer shell, said shells being axially displaceable in relation to each other, said shells having inlet openings on one of their ends for the condensate to enter a space defined by the inner walls of said inner shell, each of said shells having also ports in said sidewalls for the flow of the condensate from said space to the outlet of the valve,

an axially displaceable tube extending through said shells and being coaxial therewith, said tube being firmly attached to said inner shell for axial displacement thereof,

connecting means between said membrane means said tube for said axial displacement of said tube and shell by the membrane means, and

control means operationally connected to the other of said shells for rotational movement of said other shell about its axis, said axial displacement of one of said shells and said rotational movement of the other of said shells determining the relative position of the port of one of said shells to the port of the other of said shells.

2. A control valve as recited in claim 1, also comprising a cylindrical portion of said valve body coaxial with said shells and disposed to receive said shells.

3. A control valve as recited in claim 1, wherein said control means for rotating said outer shell comprise a spindle rotatably disposed in a portion of said valve body, a control knob disposed on the outside of said valve body and firmly connected to one end of said spindle for rotation thereof, a set of gears having two meshing toothed wheels one of which being firmly attached to the other end of the spindle, the other wheel being connected to the outer shell for transmitting rotational movement of the knob to the outer shell for alignment of said ports.

4. A control valve as recited in claim 3, also comprising indicator means connected with said control knob for indicating the angular displacement of the port of the outer shell.

5. A control valve as recited in claim 1 in which said connecting means comprises:

a piston movably disposed in said valve body and being coaxial with said shells but normally removed therefrom, said outer shell having an opening facing said piston, said piston having an outer surface facing said opening, said piston having wall means defining an inner space within said piston with an inner surface disposed opposite to said outer surface, capillary conduit means disposed in said wall means and connecting said inner space with said condensate inlet,

said tube having a first opening connecting the inside of the tube with the inner space of said piston and a second opening remote from the first one connecting the inside of the tube with the outlet of the valve,

first spring means biasing the piston in the direction of the shell opening, second spring means biasing said tube in the direction of said membrane, an axially movable rod disposed coaxially in said tube; third spring means biasing said rod in the direction of said membrane, a stopper firmly attached to said rod close to one end thereof for closing of said second opening of said tube, and

a pusher interposed between said membrane and said tube and said rod for transmitting movement of the membrane in one direction to said rod and said tube,

said outer surface closing said opening of the outer shell through the action of the first spring means after the pressure of the condensate acting on the inner surface of the piston has increased by the flow of condensate into the inner space of said piston while the ports of the shells and the second opening of said tube have been closed due to the biasing action of respective springs and in consequence of the movement of the pusher in the direction of the membrane.

6. A control valve as recited in claim 5, also comprising a membrane space defined by the inner walls of said membrane washer and a portion of said valve body, and conduit means connecting said first outlet to said membrane space for supply of condensate thereto.

7. A control valve as recited in claim 6, wherein said valve body has an upper portion containing said membrane washer and a lower portion containing said first outlet, said upper por-

Claims

1. A valve for control of circulation of a condensate, comprising: membrane means actuable by pressure in response to temperature changes, an elongated valve body coaxial with the membrane means and having an inlet and an outlet for the condensate, an outer tubular shell and an inner tubular shell disposed in said valve body and coaxial therewith, said inner shell being telescopically disposed within the outer shell, said shells being axially displaceable in relation to each other, said shells having inlet openings on one of their ends for the condensate to enter a space defined by the inner walls of said inner shell, each of said shells having also ports in said sidewalls for the flow of the condensate from said space to the outlet of the valve, an axially displaceable tube extending through said shells and being coaxial therewith, said tube being firmly attached to said inner shell for axial displacement thereof, connecting means between said membrane means and said tube for said axial displacement of said tube and shell by the membrane means, and control means operationally connected to the other of said shells for rotational movement of said other shell about its axis, said axial displacement of one of said shells and said rotational movement of the other of said shells determining the relative position of the port of one of said shells to the port of the other of said shells.

5. A control valve as recited in claim 1 in which said connecting means comprises: a piston movably disposed in said valve body and being coaxial with said shells but normally removed therefrom, said outer shell having an opening facing said piston, said piston having an outer surface facing said opening, said piston having wall means defining an inner space within said piston with an inner surface disposed opposite tO said outer surface, capillary conduit means disposed in said wall means and connecting said inner space with said condensate inlet, said tube having a first opening connecting the inside of the tube with the inner space of said piston and a second opening remote from the first one connecting the inside of the tube with the outlet of the valve, first spring means biasing the piston in the direction of the shell opening, second spring means biasing said tube in the direction of said membrane, an axially movable rod disposed coaxially in said tube; third spring means biasing said rod in the direction of said membrane, a stopper firmly attached to said rod close to one end thereof for closing of said second opening of said tube, and a pusher interposed between said membrane and said tube and said rod for transmitting movement of the membrane in one direction to said rod and said tube, said outer surface closing said opening of the outer shell through the action of the first spring means after the pressure of the condensate acting on the inner surface of the piston has increased by the flow of condensate into the inner space of said piston while the ports of the shells and the second opening of said tube have been closed due to the biasing action of respective springs and in consequence of the movement of the pusher in the direction of the membrane.

7. A control valve as recited in claim 6, wherein said valve body has an upper portion containing said membrane washer and a lower portion containing said first outlet, said upper portion also containing a second outlet connected to said conduit means, said membrane space being disconnected from said first outlet by movement of said upper portion relative to said lower portion.