US2693930A

US2693930A - Electromagnetic reversing valve

Info

Publication number: US2693930A
Authority: US
Inventors: Carnie M Carter
Original assignee: M T GOSSETT
Current assignee: M T GOSSETT
Priority date: 1949-07-20
Filing date: 1949-07-20
Publication date: 1954-11-09
Anticipated expiration: 1971-11-09

Description

2,693,930 ELECTRoMAGNETIc REvERSlNG VALVE Carnia M. Carter, Nashville, Tenn., assignor of fifty-oney per cent to M. T. Gossett, Nashville, Tenn. Application July zo, 1949, seriaiNo. 105,783 Y z Claims. (c1. 251-44) The present invention relates to new and useful improvements 1n reversing valves and more particularly to `an electromagnetic reversing valve to reverse or change direction of ow of refrigerant gases within a refrigerating system.

An important object of the valve is to provide a positive, convenient and simple control to the act of reversing the refrigerant cycle in any reverse cycle refrigerating system.

Another object is to provide a device of this character of simple and practical construction, which is efficient and reliable in operation, relatively inexpensive to manufacture and otherwise well adapted for the purposes for which the same is intended.

Other objects and advantages reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming part hereof, wherein like numerals refer to like parts throughout, and in which:

Figure 1 is a side elevational view of the valve;

Figure 2 is a vertical sectional view showing the reversing plunger in raised position;

Figure 3 is a similar view showing the plunger in a lowered position;

Figure 4 is a transverse sectional view on a reduced scale taken on a line 4-4 of Figure 2, and

Fi3gure 5 is a similar view taken on aline 5-5 of Figure Referring now to the drawings in detail wherein for the purpose of illustration I have disclosed a preferred embodiment of the invention, a valve body is designated at 1 and is constructed of suitable material and machined inside to receive a steel sleeve 2 pressed in and made gas tight. The sleeve is machined to provide upper and

lower cylinders

3 and 4, the upper cylinder being of increased diameter to receive an enlarged upper piston forming head 5 of a plunger 6 forming a lower piston which works in lower cylinder 4.

Exterior of plunger 6 and interior of cylinder 4 are finished to polished surfaces with very small clearance so that when covered with a light lm of oil, as in a refrigerating system, very little or no gas can pass from one point to another along the walls of the cylinder. Head 5 and cylinder 3 do not have quite so close a clearance, as the operation of the valve depends on a very small amount of gas passing from bottom to top of plunger head 5 in cylinder 3. The head 5 may be spaced from the top of the cylinder 3, when said plunger 6 is fully raised, by a small teat 5 on said head.

The lower portion of body 1 is provided with

ports

7, 8, 9 and 10 at 90 with respect to each other and connected to lower cylinder 4 by aligned ports 7a, 8a, 9a and 10a in sleeve 2.

Plunger 6 is formed with upper and lower pairs of circumferential slots 11 and 12.

A passage 13 is drilled through sleeve 2 and body 1 at an angle, commencing at bottom of upper cylinder 3 and ending in port 9. Behind steel sleeve 2 and in line with port 7 are upper and

lower grooves

14 and 15 cut in body 1 from top to bottom of the body. At the top, the groove 14 is notched as at 16 to coincide with port 17 drilled in valve head 18 secured on top of body 1. The port 17 leads to the bottom of a central chamber 19 in head 18 and in the lower portion of which a plug 21 is threaded having a vertical orifice 20 with a valve seat 20a at its upper end.

To one side of plug 21 a small passage 22 is drilled "ice '- through head 18 to its bottom and extending to the-top of cylinder 3 above. plungerhead 5.

The head 1s is brass and is driued and tapped to' receive a magnet plunger housing assembly 23 having v a neck 24 threaded to the top of head 18.

An electromagnetically operated valveV 32 is mounted in assembly -23 and includes a magnet plunger 25, stationary magnet 26, magnet coil 27, coil `cover 28, cover stud 29, cover nut 30, needle '31 extending upwardly from lvalve 32 and all of which follow the well known L. electromagnet principle andare of conventional construction and arranged to open and close the valve 32 with valve seat 20a. The electromagnetically operated valve is used in connection with this invention only as a means of operating pilot lines through the ports.

A square key 33 of sufficient length to guide the plunger 6 through full length of its travel is pressed into a groove 34 in lower end of steel sleeve 2 in direct line with suction port 7. Key 33 slides in a keyway 35 cut into plunger 6 and extending from the bottom of the plunger into line port 7a in sleeve 2 which coincides with suction connection 7 when plunger is at top posit1on.

Between body 1 and head 5 is a head gasket 36 and between body 1 and a base plate 37 is a base plate gasket 38.

In the operation of the device, the discharge or high pressure line of a reverse cycle refrigeration or air conditioning system is connected to port 9 and the suction or low pressure line is connected to port 7.

Ports

8 and 10 are also connected in the system to accomplish a reverse llow of fluid and are alternately connected to

ports

7 and 9, as indicated in Figures 4 and 5, during the reversing action of the valve.

The area 39 above head 5 of plunger 6 is equal to the combined area 40 under the shoulder of head 5 plus area 41 under the bottom plunger 6. Since area 40 is always subjected to high pressure from port 9 entering passage 13, and area 41 is always subjected to low pressure from port 7 and passage 15, the combined moving force of these two pressure areas is always acting to raise plunger 6 to its top position. A small teat 41 may be provided on the bottom of plunger 6 to space said area 41 from the gasket 38 when the plunger 6 is' fully lowered, and for a purpose which will be clear.

When orice 20 is closed by valve 32 and high pressure allowed to build up in area 39, due to the loose lit of head 5 in cylinder 3, the acting force of high pressure on area 39 overcomes the combined acting force of high pressure on area 40 and low pressure on area 41 and plunger 6 is accordingly pushed downwardly to the position shown in Figure 3. Slot 11 then connects port 9 with port 10 and port 8 with port 7, as shown in Figure 5, to reverse the ow.

When valve 32 is raised to open orifice 20 and allowing pressure on area 39 to become equal to pressure on area 41, then acting force of high pressure on area 40 plus low pressure on area 41 overcome the acting force of low pressure on area 39 and plunger 6 is raised and held in its uppermost position. Slot 12 then connects port 7 with port 10 and port 8 with port 9.

Having described the invention, what is claimed as new 1s:

1. In a uid flow reversing valve, a valve body including a lower cylinder having a closed lower end, and an upper relatively larger cylinder, a lower piston of the same diameter and substantially the same length as said lower cylinder working in said lower cylinder and having an enlarged piston on its upper end working in said upper cylinder, first and second pairs of diametrically opposite ports in said lower cylinder arranged in pairs in angular relation, the ports of the irst pair communicating with said lower and upper cylinders respectively below said pistons and being adapted to admit liuid under low and high pressure to said cylinders respectively, said lower piston having a bottom low pressure area constantly exposed in said lower cylinder to low pressure and tending in response to low pressure against the same to raise said pistons, said upper piston having a bottom high pressure area tending in response to high pressure against the same to raise said pistons ageaaaao,

to permit uid underhiglrk pressure. to bieeclupwardly past said upper pistontto-accumulate above the same and act against said top areaf to. lower said pistons, meanson saidy lower pistoni alternately.- connecting the ports of the irst pair with the'ports offthefsecond:pair` when said pistons-.are raised and loweredirespectively,

the ports of` saidipairsfbeingadapted when alternatelyA connected byfsaid means ,to establish reverse. iiow1 paths forvpassng liquid through said lower cylinder,- and valve controlled passage means. in said bodyv for vequalizinge pressure, accumulated above. said upper pistom Witlil'.l

that:.below` said lower: piston to permit' raising =o2said 4f, pistons in response to high and low pressures' acting against-said" bottomr` higlr and low'pressure'- areas'.l

2. A valve according to claim 1, said passage means comprising a pressure equalizing passage in said body extending from the closed end of said lower cylinder to the top of the upper cylinder.

References. Cited in the ile of this patent UNITED STATES PATENTS Number Name Date 685,930' Nethery Nov. 5, 1901 2,329,001 Robinson .Sept. 7, 1943 2,379,181 Pontius June 26, 1945 2,489,450 Crookston Nov. 29, 1949 2,550,723 Ross May 1, 1951