US1802486A - Refrigerating apparatus - Google Patents

Description

April 28, 1931. o. M. SUMMERS 8 REFRIGERATING APPARATUS Filed July 19, 1926 2 Sheets-Sheet l IrIsU/aZ /OH Imulalzbn 2 68- 7 @MMM 69 m I/1su/aZ /bn April 28, 193 o. M. SUMMERS REFRIGERATING APPARATUS 2 Sheets-Sheet 2 Filed July 19, 1926 Insu/a iforz Patented Apr. 28, 1931 or'ro M. surname, or DAYTON, omo, ASSIGNOB, BY imam: assmmnm'ra' 'ro oonrona'rxon, A oonromrron'or DELAWARE a 1 un's PA-rrur omen mmomia'rmo- APPARATUS le-3m cleanly aQize. seriarmi. 123,420. v

The present inventionfrelatesto pressure responsive electric j switches, and more particularly to switches for controlling electricallyoperated refrigerating apparatus.

On'e of the objects of the resent inven-' tion is to provide for the quic and positive operation of the movable switch contact into n and out of engagement with the stationary contact, by the usey fa sim lified mechanism which may be produce at relatively low cost;

Another object of the inventionis to rovide in a moresimple manner indepen ent adpistnients ofthe'pressures at which the switch contacts'are engaged and separated.v

one. manner of carrying out the foregoing objects is to lprovide a H contact operating member mafia cooperating actuating member and provide for translatory, relative movement between these members whereby the movable contact is actuated in a certain direction when theniemb ers are in a certain" relative po's1t1on, a nd 1S actuated 1n another direction after a 1certa1ntransl'atory, relative movementha-s takeniplacej. An adiustable, mechanical resistance element is rendered 'effective' to resist said translatory movement throughout a certain portion of said movement in one direction and then is rendered ineffective throughout another portion of said movement in jtl esame direction. second adjustable mechanicalresistance element is used tooppose translatory movement in the opposite direction; Thus, independent adjustments. may be made for the purpose of settingthe switch to close at a certainhigh pressure corresponding to ;a certain high temperature in'the' cooling unit or chamber,

and to open at a certainilow pressure corresponding to a certa n low temperature.

The present invention contemplates the use of apressure operated device for actuat-f ing switch and int-his invention a collapsible pressure respons ve device such as a metal bellows is utilizedi Due to the manufacture of this ypeof device, the tension ofv all arenot uniform. One of the objects of the presentinvention is to provide simple means for adjusting'thecollapsible device.

Further objects and advantages of the arrow'6 of Fig. 2, and

the accompan drawings, wherein a pre- I ferred form 0' embodiment of the present invention is clearly sho'wn.

In thedrawings: 4 I Fig. 1 is a top plan viewof the improved switch. I if v Fig. 2 is a partly elevational and'partly sectional View of the switch, the sectional portion being taken on line. 2--2 of Fig. 1.

Figs. 3 and 6 are fragmentary views, partly in section each" showin the operating.

ollowing description, reference being had to i mechanismin dilferentpos tions from that 7 shown in the other figures Fig. 4 isa fragmentary view partly in section as the bottom portion of the switch, the

view being taken looking inrthedirection of F ig. 5 is a view similar to Fig; 2 but show ing operating' mechanism in a dlfiGlQIltiPOSltion fromthatshown in Fig.2.

Fig. 7 is an end'view of the switch. Referring'gto the drawings, there is shown a frame 20 having downwardy bent supporting legs 21 and a platform 22Which carries the entire switch mechanism. At one end of the platform 22 there are a plurality of perforations, each including a relatively large opening 23 and a relatively small opening 24. The openings 23 are each adapted to receive one of the legs 25- of a cage 26. The

legs 25 are constructed of resilient material and normallytend to bend outwardly and each is provided with a cut-a-way portion adapted to. form shoulders 27 and 28. Centrally located with respect to the openings 23,

the platform 22 isprovided with an opening 29 which merges into a larger opening'BO. A metal bellowsBl is supported by the platform 22 and is providedrwith a nipple 82 which extendsthrough the opening 29. A fluid conductor 33 connects the interior of the bellows with a coupling 34. Bellows 31, fluid conductor pipe 33, and coupling 34, are constructed as a sub-assembly, the opening 30 within platform 22'being of suchdiameter so as to permit the coupling 34 to be inserted thercth'rough. After the coupling 34 and pipe 33 have been inserted downwardly through the opening 30, the bellows 31 and nipple 32 are shifted to the right to the position shown in the drawings. The cage 26 is then placed in position by first bending the legs inwardl and then inserting same within the openings 23 until the cut-away portions thereof are opposite the opening 24; the legs are then permitted to spring outwardl whereby the cut-a-way portions move into t 1e opening 24. The shoulders 27 and 28 on opposite sides of the platform 22 will prevent the upward or downward movement of the cage 26. A plate is mounted on the underside of the platform 22 and is of sufficient diameter to prevent the lateral displacement of the legs 25. Plate 35 is provided with connecting openings 36 and 37 the opening 36 being adapted to receive the nipple 32 and the opening 37 being of sulficient diameter to receive the coupling 34 whereby the plate may be placed in position from the bottom side of the platform 22. A nut 38 is utilized for holding the plate 35, the nipple 32, and likewise the bottom portion 40 of the bellows 31 in position. The upper part of the cage 26 has a shoulder 42 for limiting the movement of the bellows thus preventing abnormal expansion of bellows 31.

The cage also carries a plurality of ears 43 which carry a pin 44, upon which an operating member or lever 45 is pivotally mounted. The operating member 45 is pivotally connected by a pin 46 to the top wall 47 of bellows 31 and is adapted to be moved upwardly and downwardly in response to the pressure within the bellows 31.

The opposite end of platform 22 carries an inverted U-shaped bracket, or yoke 50. A roller bracket 51 is ivotally mounted upon a pin 52 carried by the yoke 50. A spring 53 is wound around the pin 52 and tends to yieldingly move the roller bracket 51 to the right as viewed in the drawings. Roller bracket 51 carries a roller 55 which is arranged to cooperate With camming surfaces 56 and 57 of a lever 58 which lever is pivotally mounted at 59 upon the operating member Lever 58 comprises two sheet metal strips 60 which a ."e spaced from one another by a spacer rivet 61 and by a member 62 having the camming surfaces 56 and 57. These strips 60 are located on opposite sides of the arm 45. The end of the lever opposite the member 62 carries a link 64, which link is connected by clips 65 with a contact 66. Gontact 66 is pivotally mounted at 67 upon a plate 68 carried by an insulating block 69. The contact 66 is also provided with a stop member 70 adapted to engage the block 69 to limit the upward movement of contact 66. A nonarcing contact 71 is carried by a leaf spring 72 which in turn is secured to the contact 66 and spring 72 normally tends to maintain the non-arcing contact 71, in the position relative to contact 66, as shown 1 Figs. 2 and 6. The insulating block 69 also carries a contact 74 adapted to be engaged by contacts 66 and 71. Wires 75 and 76 are connected re spectively with contacts 66 and 74.

The top wall 78 of yoke 50 carries a screw threaded bushing 79 held in place by nut 80. Bushing 79 is arranged to receive a plunger 81 having a shoulder 82 for limiting the downward movement thereof. Bushing 79 screw threadedly carries a cap 83. and a spring 84 is interposed between the cap 83 and the shoulder 82 and normally tends to move the plunger downwardly. Plunger 81 lies in the path of the movement of a head 85 of operating member 45.

A rod 87 extends through an opening in platform 22 and is pivotally connected at 88 with the member Adjusting nuts 89 and 90 co-operate with the rod 87 and are located on the opposite sides of platform 22. A

spring 91 is interposed between nut 89 and platform 22 and a spring 92 is interposed between nut 90 and platform 22. Spring 91 may be used to assist the bellows 31 in the upward movement of lever 45 or the spring 92 may be used to resist the movement of bellows 31. Due to manufacture. some bellows may have different tension than others. Therefore. it may be necessary to assist the bellows, or it may be necessary to resist the bellows. \Vhen it is necessary to aid the bellows, the nuts 90 are moved to release the tension of spring 92. Then by screwing the nuts 89 downwardly the tension of spring 91 can be increased. thus assisting the bellows.

However, if the tension of the bellows per se is greater than that desired. the nuts 89 are screwed upwardly to render the spring 91 ineffective. Then, the nuts 90 are screwed upwardly to increase the tensions of spring 92 so that said spring resists the tension of the bellows. In this manner the tension of the bellows is readily regulated.

The present invention is particularly adaptable for controlling system in which it is desirable to provide independently high and low pressure adjustments. such as a refrigerating system. One particular use of this switch would be to connect the switch so that the bellows 31 would be responsive to the pressure within the low pressure side of a refrigerating system. the switch being adaptedto interrupt the circuit to a compressor driving niotor when the pressure within the low pressure side attains a certain low value and to complete the circuit to the motor when the pressure within the low pressure side attains a ccrtain high value.

The operation of the switch is as follows, considering that the contact 66 has just separated from contact 74 the switch mechanism will be in a position substantially as shown in Fig. 2. As the pressure increases within the bellows 31 the lever 45 will be moved upwardly. The spring pressed plunger 81 lying within the path of movement of the head 85 of lever 45 will restrain the upward movement of lever 45. As the member 45 moves upwardly the lever 58 will be moved translatedly upwardly. The stop 70 of the contact 66 being in engagement with block 69, will limit the upward movement of that end-of the lever 58 which carries the link 64, then, on further upward movement of member 45, lever 58 will pivot about the connecting pin 95, between link 64 and lever 58. This movement of lever 58, will cause the carnming surface 56 to move the roller bracket 51 toward the left. l-Vhen the apex of member 62, which is formed by the surfaces 56 and 57, engages the roller 55 the levers 58 and 45 will be substantially in position shown in Fig. 6 in which position contact 66 is still separated from contact 74. Upon further upwardly movement of the levers 45 and 58 the camming surface 57 will be moved into engagement with the roller 52 at which time spring 53 will exert its yielding force to rotate the lever 58 in a clockwise direction, and, since the lever 58 is free to rotate, the roller acting on camming surface 57 will cause contact 66 to quickly engage contact 74. With the construction and arrangement of pivoted contact 66, link 64, lever 58 and fulcrum pin 59 relative to one another, as shown, the spring 53 exerts its yielding force to firmly maintain contact 66 in engagement withcontact 74, as shown in Fig. 5.

As the pressure within the bellows 31 recedes, the member 45 will move downwardly (see Fig. 5) and that end of lever 58, which is connected with link 64, is held substantially stationary because contact 74 limits the downward movement of contact 66 and likewise link 64. Therefore, with further downward movement of member 45, lever 58 will pivot about pin 95. The camming surface 57 will then move downwardly over roller 55 and when the apex of member 62 moves beyond the roller, spring 53 will co-operate with surface 56 to rotate lever 58 about its fulcrum pin 59. The tension of spring 53 is such as toquickly rotate lever 58 thereby suddenly separating contacts 66 and 71 from contact 74. Non-arcing contact 71 will separate from contact 74 after contact 66 thus preventing the burning of contacts 66 and 74. \Vhen the apex of member 62 engages the roller 55, a condition arises in which the spring 53 will not urge lever 58 in either direction and there may be a tendency for lever 58 to oscillate. This oscillating movement, however, is not imparted to contacts 66 and 71 and said contacts are not separated from contact 74 until the apex has moved beyond the roller 55 at which time surface 56 will engage roller 55 to function as previously stated; Fig. 3 shows the relative relations of the elements just after the apex has moved downwardly beyond the roller 55. Referring to this Fig. 3 it is apparent how the contacts 66 and 71 are maintained firmly against contact 74. A relative large hole 96 is provided in link 64 for receiving a pin 97, by which the link 64 is connected with clips 65 of contact 66, which pin 97 is free to move vertically within said hole 96. A hole 98 is also provided within the link 64 and is disposed transversely to hole 96 and adapted to receive a spring 99. Spring 99 is disposed between the top of hole 98 and pin 97 and urges pin 97 and likewise contact 66 downwardly. By virtue of this construction, the spring 99 maintains contact 66 in engagement with contact 74 although the lever 58 is in such a position with respect to roller 55 that it tends to oscillate.

It is apparent from the description and particularly Figs. 3 and 6 that a switch has been provided in which contacts are engaged and separated quickly. This is accomplished by providing a floating fulcrum pin 59 for the lever 58 whereby the lever 58 is translatedly moved relative to the roller 55. With this construction there is provided mechanism in which a lever and an actuating roller have different dead center positions when the lever is translatedly moved in opposite direction. In this manner one dead center posi tion is attained while the contacts are separated and just previous to their engaging movement and a second dead center position is attained while the contacts are still in engagement and are about to be separated. Thus the movable contact is retained in either of its two positions until the actuating mech" anism therefor has moved beyond dead center position. In this manner quick action of the contact in either direction is insured.

By utilizing mechanism in which the fulcrum point (pin 59) must be moved to a certain position before the contact actuating lever is moved to actuate the contact and which must be moved to a different position in order to reverse the movement of said lever, it is possible to provide for independent high and low pressure adjustments. During the latter part of the downward movement of member 45 (see Figs. 2 and 5), the plunger is not in engagement with the member 45. Therefore, spring 84 is not effective and the pressure at which the contacts separate can be regulated by either of springs 91 and 92. During the upward movement, however, member 45 engages plunger 81. Thus the pressure at which the contacts close is regulated by the adjustment of the tension of spring 84. In this manner the switch can be adjusted so that the contacts can be closed at any desired pressure independently as to the pressure at which the contacts are open and, vice versa. To adjust the switch the spring 91 or 92 is set so that the contacts are opened at the desired pressure within the bellows 31. Then spring 84 is set so that the contacts are closed at the desired pressure within the bellows 31.

t i hile the of embodiment of the present invention as herein disclosed, constitutes a preferred form. it is to be understood that other forms might be adopted, all coming 3 within the scope of the claims which follow.

hat is claimed is as follows:

1. A switch comprising, in combination, a contact actuating lever member, an actuating member for the lever member, one of said members having a plurality of cammin surfaces, and the other of said members eing adapted to cooperate with one of the cammingsurfaces and thereby tending to yieldingly maintain the lever member in a certain position throughout a certain bodily movement of one of said members with respect to the other and being adapted to cooperate with another of said ca-mming surfaces for quickly rocking said lever member when the members are relatively bodily moved to a certain position, and means for bodily moving the lever member relative to the actuating member. v

2. A switch comprising, in combination, a

. contact actuating lever member having a plurality of camming surfaces, an actuating member adapted to cooperate with one of the camming surfaces and thereby tending to yieldingly maintain the lever member in a certain position throughout a certain bodily movement of one of said members with respect to the other and being adapted to co-- operate with another of said camming surfaces for quickly rocking said lever memher when the members are relatively bodily moved to a certain position, and means for bodily moving the lever member relative to the actuating member.

3. A switch comprising, in combination, a contact actuating lever member, mechanism including an actuating member adapted to yielding'ly maintain said lever member in a certain position through a certain bodily movement of one of said members with respect to the other and thereafter quickly move the lever member to another position, means for bodily moving one of said members relative to the other, and means for yieldingly resisting the movement of the first means throughout a certain portion of the movement thereof and being ineffective throughout another portion of the movement of said first means.

4. In a switch, the combination with a supporting frame, of a pressure responsive device having a movable wall and an, operating member associated therewith, a cage for'said device including legs extending through openings Within the frame and each having shoulders engaging opposite sides of said frame, and common means for preventing lateral movement of said legs.

5. In a switch, the combination with a supporting frame, of a pressure responsive device having a movable walland an operating frame, and a plate etween said legs for preventing lateral movement of the latter.

6. In a switch, the combination with a supporting frame, of a pressure responsive device having a movable wall and an operating member associated therewith, a cage for said device including le s extending through openings within the rame and each having shoulders engaging opposite sides of said frame, a plate between saidlegs for preventing lateral movement of the latter, and common means for maintaining said plate and said device in position.

7. In a switch, in combination with a sup porting frame; of an operating member; a unit including a pressure responsive device located on one side of the frame and having a movable wall associated with said member, a couplin located on the opposite side of frame, an a conductor connecting said coupling and device; a cage for said device including legs extending through openings within the frame and each having shoulders engaging opposite sides of the frame; a plate interposed between said le s for preventing the lateral movement of said legs: and means for maintaining said plate and said device in'position, said plate and frame having openings permitting the passage of the coupling therethrough whereby said device, conductor, and coupling may be removed as a unit.

8. In a switch, the combination with'an operating member; a pressure responsive device having a movable wall associated with said member; a support; and means for ad- 'usting said device includin a movable member extending through said support, adjust able members on opposite sides of said support each co-operating with the movable member, and a plurality of yielding means connected between the adjustable members and the support.

9. In a switch, the combination with an operating member; a pressure responsive device having a movable wall associated with said member; a su port; and means for adjustifig said device including a movable member extending through said support, adjustable members on opposite sides of said support each co-operating with the movable member, and springs on opposite sides of the support, each spring being interposed between the support and an adjustable member.

10. A switch comprising. in combination, a movable contact, a lever for actuating said contact, means for snapping said lever to opencontact position, said means having a dead center with the lever, a lost motion connection between said lever and contact including a loosely fitting connecting pin, and a spring engaging said pin for yieldingly maintaining said contact in closed position while said lever and means are in dead center position.

11. A switch comprising, in combination, a contact actuating lever member, an actuating member for the lever member, one of said members having a plurality of camming surfaces, and the other of said members being adapted to cooperate with one of the camming surfaces and tending. to yieldingly maintain the lever member in a certain position throughout a certain bodily movement of one of said members with respect to the other and being adapted to cooperate with another of said camming surfaces for quickly rocking said lever member when the members are relatively bodily moved to a certain position, means for bodily moving one of said members relative to the other, and a resistance device arranged to resist movement of said means when the said other member cooperates with one of the camming surfaces and being inefiective throughout the latter portion of the movement between the saidother member and the other of the camming surfaces.

12. A switch com rising, in combination, a contact actuating ever member having a plurality of camming surfaces, an actuating member for said lever member adapted to cooperate with one of the camming surfaces and thereby tendin to yieldingly maintain the lever member in a certain position throughout a certain bodily movement of one of said members with respect to the other and being adapted to cooperate with another of said camming surfaces for quickly rocking said lever member when the members are relatively bodily moved to a certain position, means for bodily moving one of said members relative to the other, and a resistance device arranged to resist movement of said means when the said other member cooperates with one of the camming surfaces and being inetiective throughout the latter portion of the movement between the said other member and the other of said camming surfaces.

13. A switch comprising, in combination, a movable contact a lever for actuating said contact, means for snapping said lever to open contact. position. said means having a dead center with the lever, a lost motion connection between said lever and contact including a hollow link. a spring within the hollow link, a loosely fitting connecting pin, said spring engaging the pin for yieldingly maintaining said contact in closed position while said lever and means are in dead center position.

14. A switch comprising, in combination. a movable contact. a lever for actuating said contact, means for snapping said lever to open contact position. said means having a dead center with the lever. a lost motion com nection between said lever and contact including a hollow part, a coil spring within said hollow part, a connecting pin loosely connected with said part and extending transversely to said coil spring, said spring engaging the pin for yieldmgly maintaining said contact in closed position while said lever and means are in dead center position.

15. A switch comprising, in combination, a plurality of contacts, a contact actuating member connected with one of said contacts and movable in opposite directions, means for resisting movement of said actuating member including a spring and a member engaged by the spring and lying in the path of movement of the actuating member, an externally threaded member and an internally threaded member coopc 'ating to provide a casing for said spring, one of said threaded members engaging said spring and being adapted to vary the tension thereof.

16. A switch comprising, in combination, a plurality of contacts, a contact actuating member connected with one of said contacts and movable in opposite directions, means for resisting movement of said actuating member including a spring and a plunger having a shoulder engaged by the spring and arranged in the path of movement of the actuating member, an externally threaded member and an internally threaded member cooperating to provide a casing for said spring and adapted to receive the plunger, one of said threaded members engaging said spring and being adapted to vary the tension thereof.

17 A switch comprising, in combination, a plurality of contacts, a contact actuating member connected to one of said contacts and movable in opposite directions, means for resisting movements of said actuating member including a spring and a member engaged by the spring and lying in the path of movement of the actuating member, said spring engaged member having a shoulder for limiting the movement thereof, an externally threaded member and an internally threaded member cooperating to provide a casing for said spring, one. of said threaded members engaging said spring and being adapted to vary the tension thereof.

18. A switch comprising. in combination, relatively stationary and movable contacts, a quick break device for said contacts including a lever member associated with the movable contact, an actuating member associat ed with said lever member, means for bodily moving one of said members relative to the other, said actuating member having a dead center position with the levermember and tending to hold said lever member in contactmaking position until said means has moved said members to the dead center position and tending to quickly move said lever member to actuate the movable contact after said means has moved the members beyond the dead center position, and spring means between the lever member and movable contact for maintaining said movable contact in engagement with the other contact when said members are in dead center position.

19. A switch comprising, in combination, relatively stationary and movable contacts, a quick break device for said contacts including a lever member associated with the movable contact, an actuating member associated with said lever member, means for bodily moving one of said members relative to the other, said actuating member having a dead center position with the lever member and tending to hold said lever member in contact-making position until said means has moved said members to the dead center position and tending to quickly move said lever member to actuate the movable contact after said means has moved the members beyond the dead center position, and means for maintaining said contacts in engagement while said members are in dead center position, said last means including a spring constantly urging the contacts toward one another.

In testimony whereof I hereto afiix my signature.

OTTO M. SUMMERS.

Images