US3074346A

US3074346A - Electrically operated pumps

Info

Publication number: US3074346A
Application number: US2179A
Authority: US
Inventors: Jackson Harold Ernest
Original assignee: Tecalemit Ltd
Current assignee: Tecalemit Ltd
Priority date: 1959-01-16
Filing date: 1960-01-13
Publication date: 1963-01-22
Anticipated expiration: 1980-01-22

Description

1963 H. E. JACKSON 3,074,346

ELECTRICALLY OPERATED PUMPS Filed Jan. 13. 1960 4 Sheets-Sheet 1 Fig.1]

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ATToa/vmg Jan. 22, 1963 Filed Jan. 13. 1960 H. E. JACKSON ELECTRICALLY OPERATED PUMPS 4 Sheets-Sheet 2 INVENTOR 5 Y WTPMWMW ATTORNE 3 Jan. 22, 1963 H. E. JACKSON ELECTRICALLY OPERATED PUMPS 4 Sheets-Sheet 3 Filed Jan. 13. 1960 BY M I Mun-n1 2 3 ATTORNE Y3 Jan. 22, 1963 H. E. JACKSON 3,

ELECTRICALLY OPERATED PUMPS Filed Jan. 15. 1960 4 Sheets-Sheet 4 //v vE/vToR /na 5/065 Jacka M, mjmfl ATTORNE Ya! United States Patent 3,074,346 ELECTRICALLY OPERATED PUMPS Harold Ernest Jackson, St. Maurice, Devon, England, assignor to Tecalemit Limited, Devon, England Filed Jan. 13, 1960, Ser. No. 2,179 Claims priority, application Great Britain Jan. 16, 1959 10 Claims. (Cl. 1t)353) This invention relates to electrically-operated pumps for fluids, particularly for liquids. It is more especially concerned with the provision of an improved fuel pump for supplying petrol or other fuel to an internal combustion engnie, although it is applicable to pumps used for many other purposes.

Fuel pumps for internal combustion engines commonly comprise a diaphragm which is operated in one direction by means of an electro-magnet and in the other direction by a spring, the pump also including a valve arrangement and contacts controlling the current supply to the magnet, such that the diaphragm is reciprocated to effect pumping of the fuel until the pressure on the delivery side reaches a predetermined value.

It is one of the objects of the present invention to pro vide improvements in pumps of this type, with particular reference to the electrical contact mechanism of the pump, while the invention is also concerned with the provision of improvements in the pumps for other purposes.

According to the invention, the electrically-operated pump comprises a diaphragm or other pumping member, which is reciprocated in a pumping chamber by means of an electro-magnet having a main armature which is connected with the pumping member and which is operated against a resilient force, such as the force of a spring, contact mechanism which controls the current to the electro-magnet and comprises a fixed contact, a movable contact which is carried by (or forms part of) a contact carrier and which is biassed away from the fixed contact to break the circuit of the electro-magnet but which is adapted to be drawn into engagement with the fixed contact by the said resilient force when the electro-magnet is de-energised in order to re-energise the latter, and a contact armature which tends to hold the contacts in engagement while the main armature completes at least part of its travel produced by energisation of the electromagnet.

Preferably, the contact armature is connected to or mounted on the contact carrier and is arranged to be attracted by the same electro-magnet which operates the main armature. The important requirement in any case is that the opening of the contacts controlling the main electro-magnet should be delayed for a time suflicient to allow the pumping member to make the required stroke.

According to a preferred feature of this invention the main armature is connected with the contact carrier through a lost-motion connection which allows the armature to make part of its sroke before it actuates the contact carrier.

Further features of the invention will become apparent from the following description of one constructional embodiment of the invention.

This constructional form of the invention, which is applied to a petrol pump for an automobile engine, is herein after described with reference to the accompanying drawings, wherein:

FIG. 1 is a sectional elevation of the pump;

FIG. 2 is a view of the pump, partly in section, at right angles to FIG. 1;

FIG. 3 is a plan view of the pump with the top cover removed;

FIG. 4 is a plan view of the upper contact carrier;

PEG. 5 includes a plan view and a sectional elevation of the contact armature; and

3,074,346 Patented Jan. 22., 1963 FIG. 6 is a plan view of the lower contact carrier.

Referring to the drawings:

The pump comprises upper, central and

lower body portions

1, 2 and 3, a top plate 4 and a top cover 5 and a bottom cover 6, secured to the portion 3 by a screw 6A, which parts are assembled together co-axially with each other, except that the top cover 5 may be offset laterally and shaped to accommodate contact mechanism referred to hereinafter. The upper body portion 1 is of openended cylindrical form and accommodates a solenoid the coil 7 of which is wound on a non-conductive reel or former 8. The edge of the upper flange 9 of this reel or former is clamped between the top plate 4 and the bottom of an annular recess 10 formed in the upper edge of the upper body portion 1. The lower edge of the latter is clamped against the upper edge of a flange 11 on the central body portion 2, which latter is in the form of an an nular flange disc. This clamping, which secures the top plate 4 and the three

body portions

1, 2 and 3 together, is effected by means of clamping bolts 12 which pass through holes in the top plate 4 and in the base of the central body portion 2 and the ends of which are screwed into tapped holes in a flange 13 provided on the lower body portion 3. A diaphragm 14 made of any suitable flexible material; such for example as nylon strip, is clamped between the central and

lower body portions

2 and 3, preferably with the inclusion of a sealing ring 15 fitted in a groove 16 in the flange 13 of the lower body portion.

Diaphragm backing discs 17 made of thin metal or other suitable material are fitted on the upper and lower sides of the diaphragm 14 to prevent stretching of the latter due to fluid pressure. In order to provide the necessary flexibility each backing disc is preferably formed with alternating inwardly and outwardly extending radial cuts or slots 18.

The lower body portion 3, which may be constructed as a metal die-casting, is shaped to provide a pumping space or chamber 19 below the diaphragm, which pumping space has inlet and

delivery ports

20 and 21 respectively controlled by inlet and outlet non-return valves 22 and 23 of any suitable type. The inlet valve 22 is urged on to its seat 24 by a spring 25 and the outlet valve is urged on to its seat 26 by a spring 27. Liquid admitted into a liquid containing space, formed partly in the bottom cover 6 and partly in the lower body portion 3, through an inlet duct 31 (FIG. 2) passes through a filter gauze 28, fitted between a cork washer 29 and the out-turned rim 6B of the bottom cover 6, and past the inlet valve to the pumping space 19.

Through the outlet valve 23 the outlet port 21 is adapted to be connected to a delivery pipe 30 which passes through the side wall of the lower body member 3 and through the inlet valve 22 the inlet port 20 is adapted to be connected to an inlet pipe 31A which also passes through the side wall of the lower body part 3.

The lower end of the magnet armature 32 (herein after referred to as the main armature), is connected to the diaphragm by means including an armature plate 33 and a clamping disc 34. The upper end of the armature is bored to accommodate a helical compression spring 35, the upper end of which engages a washer 36 made of an insulating material, such as Tufnol, which is fitted beneath a central hole 37 formed in the top plate 4. The force of the spring thus presses the arma ture 32, and hence the diaphragm 14, downwardly when the magnet is not energised and the spring-operated downward movement of the main armature and diaphragm effects a delivery stroke.

On the top plate 4- there is a contact assembly which is operated and controlled partly by the movement of the main armature 32 and partly by the action of a con tact armature 38, as will be described. The main armature 32 carries a central stem or push rod 39 which extends upwards inside the aforesaid compression spring 35and the upper end of which projects through the insulating washer 36 and the hole 37 in the top plate 4. The central stem 39 is formed with an annular groove 40 which engages with a D-shaped or other suitable hole or slot 41 formed in an upper contact carrier 42, FIG. 4, so that the carrier will be reciprocated upwardly and downwardly by the action of the main armature 32.

The upper and lower faces forming the ends of the groove 40 in the stem 39 are fitted with bufier washers 43 and 44, FIG. 1, which may be made of an oil-resisting rubber or other equivalent composition. The washers may engage in reduced necks formed in the groove 4i) in order to hold the washers apart against the upper and lower ends of the groove. The distance between the washers is greater than the thickness of the contact carrier 42, so as to provide a lost motion connection between the main armature 32 and the contact carrier.

The contact carrier 42, FIG. 4, which is of T-shape and partly of U-section, is formed of a resiliently flexible sheet metal, such as phosphor bronze. The ends of the cross piece 45 of the T are formed with

slots

46 and 47 to fit on a pair of studs 43, FIGS. 1 and 3, which are mounted on the top plate 4 of the pump and which support the contact carrier. Notches t) and 51 may be formed in the sides of the limb 52 of the T, where it meets the cross piece 45, in order to provide a resiliently flexible neck at this point, while stifiness may be given to the remainder of the limb 52 by bending over the edges of the latter to form

side flanges

53 and 54. The aforesaid D-shaped hole 41 is formed in the limb 52, the other end of which latter carries an up er electrical contact 55, FIG. 1, on its lower side.

The movable contact 55 engages a fixed contact 56 carried on a lower contact carrier 57 when the upper contact carrier 42 is drawn downwardly by the movement of the stem 39 when the main armature 32 is forced down by its spring 35, although the resilience of the contact carrier 42 tends to hold the

contacts

55 and 56 open. As shown in FIG. 6, the lower contact carrier 57, which may be made of mild steel, is substantially D- shaped and is formed with a substantially rectangular aperture 58 and it is mounted at one end through holes 57A upon the said studs 48. The opposite end of the lower contact carrier is formedrwith a hole 59 in which the fixed contact 56 is mounted.

The upper contact carrier 42 carries the contact armature 32, FIG. 5, which is formed from a strip of mild steel, the ends 69 and 61 of which are bent upwardly at right angles to the central portion, in the form of a U. The

ends

60 and 61 of this U-shaped armature fit in

slots

62 and 63, FIG. 4, in the upper contact carrier 42 on each side of the D-shaped hole 41 in the latter, and they are secured to the carrier. The central or base part of the contact armature is slotted or cut away at 64 in order to clear thestem 39, while the contact armature is so shaped that when it is in its lowest position, as shown in FIG. 1, with the

contacts

55 and 56 in engagement, it is close to or enters into the hole 37 in the top plate 4, above the insulating Washer 36, so that the contact armature is attracted by the electro-magnet when the latter is energised.

The fixed contact carrier 57 (FIG. 6) is formed of stilf metal and the apertur 58 surrounds and provides clearonce for the stem 39' and for the contact armature 38. The carrier 57 is mounted on the previously-mentioned studs 48, and it is electrically insulated from the studs by means of spacing sleeves 65 and Washers 66 made of insulating material, which sleeves and washers also insulate the supportirom the An electrical condenser contact carrier. 67, FIGS. 1 and 3, may be connected between the contact carrier 42 contact support 57, across the contacts.

The operation of the pump will now be described.

Assuming that the main armature 32 has been brought to its lower position by the action of the spring 35, it will, when moving to this position, have drawn down with it the contact carrier 42 so as to cause the movable contact 55 to engage the fixed contact 56, thereby closing the circuit of the electro-magnet. The resulting energisation of the latter will draw the main armature 32 and with it the pump diaphragm 14 upwardly, thus causing the pump to make a suction stroke. The electro-magnet will also attract the contact armature 38, which will hold the

contacts

55 and 56 closed during the movement of the main armature which is permitted by the lost motion connection provided by the distance between the

buffer washers

43 and 41 in the groove 49 in the stem 39.

After the main armature has moved through this distance, however, the lower butter washer 44 on the stem will engage and move the contact carrier 42 upwardly, thus opening the contacts and breaking the circuit to the electro-magnet. The main armature will then be moved downwardly by its spring 35, carrying the diaphragm to efiect a delivery stroke. During the first part of this downward movement of the main armature, the movable contact 55 will be held olf the fixed contact 56 by the resilience of the contact carrier 42, but after the upper bufi'er washer 43 in the groove 40 in the stem 39 has on gaged the contact carrier 42, continued movement of the main armature and stem will bringthe movable contact 55 down into engagement with the fixed contact 56. This will re-energise the electro-magnet to cause the pump to make another suction stroke.

The pump will continue to operate in the above manner until the delivery pressure reaches a value sutficient to prevent the spring 39 acting on the main armature 32 from effecting a further pumping stroke.

The top cover 5 which protects the contact mechanism which has been described may be secured in position by means such as by screws engaging in the top plate.

I claim:

1. A reciprocating electromagnetic motor comprising an electromagnetic frame having an axial armature opening, an electromagnetic winding carried by said frame, a first armature mounted for sliding movement in said opening from a de-energized position extending at least partially out of one end of said opening to an energized position inwardly from said de-energized position in response to the energization of said winding, means biasing said armature to its de-energized position, contact mean for controlling the current to said armature and including a fixed contact and a movable contact, a contact carrier carrying said movable contact and biasing said movable contact out of engagement with said fixed contact, a second armature of generally channel-shape having a pair of legs interconnected by a bight portion, said legs being connected to said contact carrier and said armature being axially aligned with said opening with its bight portion inwardly relative to said opening at the other end of said opening with respect to said first armature for movement between an energized position biasing said contacts into engagement and a de-energized position with said second armature moved upwardly of said opening to open said contacts in response'to the energization and de-energization of said winding, and means interconnecting said contact carrier and said first armature for moving said movable contact between an engaged and disengaged position relative to said fixed contact in response to the de-energization and energization of said winding.

2. A reciprocating electromagnetic motor as set forth in claim 1 above wherein the last-mentioned means includes a lost-motion connection between the contact carrier and the first armature permitting the armature to make at least part of its stroke before it actuates the contact carrier.

and the fixed 3. A reciprocating electromagnetic motor comprising a reel-shaped frame member having a single axial opening, an electromagnetic winding carried by said member, a first armature responsive to the energization of said winding mounted for sliding movement in said opening through one end of said opening, means for biasing said armature out of said opening, normally opened switch means including a pair of contacts and a contact carrier for controlling the energization of said winding, a second armature mounted on said contact carrier for axial movement relative to said opening responsive to the energization of said winding and connected to bias said switch means to its closed position when said winding is energized and means interconnecting said switch means and said first armature for opening and closing said switch means in response to the position of said first armature.

4. A reciprocating electromagnetic motor as set forth in claim 3 above wherein said last-mentioned means includes a lost-motion connection interconnecting said switch means and said first armature allowing said armature to make at least part of its stroke before it actuates said switch means.

5. In an electrically operated pump, the combination comprising a pumping member, a pumping chamber, an electromagnetic frame having an axial armature opening, a single electromagnetic Winding carried by said frame, a first armature responsive to the energization of said winding mounted for sliding movement in said opening and connected to reciprocate said pumping member in said pumping chamber, resilient means biasing said armature in one direction, normally opened switch means for controlling energization of said winding and including a fixed contact and a movable contact carried by a contact carrier, said movable contact being biased away from the fixed contact to break the circuit of said electromagnetic winding but adapted to be drawn into engagement with the fixed contact by said resilient means when said electromagnetic winding is de-energized in order to re-ener gize said electromagnetic winding, and a contact armature responsive to the energization of said winding biasing the contacts into engagement while the main armature completes at least a part of its travel produced by energization of said electromagnetic Winding, said contact armature being mounted on said contact carrier and being axially aligned with said opening for movement relative to said frame, said contact armature being mutually attracted to said frame by the energization of said electromagnetic winding, said contact armature being effective to delay the opening of the contacts controlling the main armature for a time sufiicient to allow the pumping member to make the required stroke, said first armature being connected with said contact carrier through a lost-motion connection which allows the armature to make at least part of its stroke before it actuates the contact carrier.

6. In an electrically operated pump, the combination comprising a pumping member, a pumping chamber, an electromagnet including a frame, a single electromagnetic winding carried on said frame, a main armature responsive to the energization of said Winding connected to reciprocate said pumping member in said pumping chamber, resilient means acting to bias said main armature in one direction, contact means which controls the current to said electromagnetic winding, said means including a fixed contact and a contact being biased away from the said fixed contact to break the circuit of said electromagnetic winding but adapted to be drawn into engagement with said fixed contact by the said resilient means when said electromagnetic winding is de-energized in order to reenergize the latter, and a contact armature responsive to the energization of said winding biasing the contacts into engagement while the main armature completes at least part of its travel produced by energization of said electromagnetic winding, said contact armature being mounted on said contact carrier and being arranged to be attracted by said electromagnetic winding which operates the main armature, said contact armature being effective to delay the opening of the contacts controlling the said electromagnetic winding for a time sufiicient to allow the pumping member to make the required stroke, said main armature being connected with said contact carrier through a lost-motion connection which allows the armature to make at least part of its stroke before it actuates the contact carrier.

7. The combination as set forth in claim 6 above wherein the pumping member includes a flexible diaphragm which is clamped at its periphery and fixed centrally to the main armature, and wherein there is provided a liquid containing space in the fuel chamber providing below it a pumping chamber which is adapted to be connected to said liquid containing space, and additionally including a valve controlled inlet port connected to said space and a valve controlled outlet port connected to said space.

8. The combination as set forth in claim 6 above wherein the contact carrier is inherently resilient tending always to move the movable contact out of engagement with the fixed contact.

9. The combination as set forth in claim 6 above wherein both said main and said contact armatures are attracted coaxially relative to an opening in said frame.

10. An electromagnet including a single electromagnetic winding, a main armature responsive to the energiZat-ion of said winding connected for reciprocal movement, resilient means acting to bias said main armature in one direction, contact means which control the current to said electromagnetic Winding, said contact means including a fixed contact and a movable contact carried by a contact carrier, said movable contact being biased away from the said fixed contact to break the circuit of said electromagnetic Winding but adapted to be drawn into engagement with said fixed contact by the said re silient means while the electromagnet is de-energized in order to re-energize the latter, and a contact armature responsive to the energization of said winding biasing the contacts into engagement while the main armature completes at least a part of its travel produced by ,energization of said electromagnetic winding, said contact armature being mounted on said contact carrier and being arranged to be attracted by said electromagnetic Winding which operates the main armature, said contact armature being effective to delay the opening of the contacts controlling the main electromagnet for a time sufficient to allow the main armature to complete at least part of its required stroke, said main armature being connected with contact carrier through a lost-motion connection which allows the armature to make at least part of its stroke before it actuates the contact carrier.

References Cited in the file of this patent UNITED STATES PATENTS 2,430,151 Whitted Nov. 4, 1947 2,505,395 Gratzmuller Apr. 25, 1950 2,706,795 Dickey Apr. 19, -5

Claims

1. A RECIPROCATING ELECTROMAGNETIC MOTOR COMPRISING AN ELECTROMAGNETIC FRAME HAVING AN AXIAL ARMATURE OPENING, AN ELECTROMAGNETIC WINDING CARRIED BY SAID FRAME, A FIRST ARMATURE MOUNTED FOR SLIDING MOVEMENT IN SAID OPENING FROM A DE-ENERGIZED POSITION EXTENDING AT LEAST PARTIALLY OUT OF ONE END OF SAID OPENING TO AN ENERGIZED POSITION INWARDLY FROM SAID DE-ENERGIZED POSITION IN RESPONSE TO THE ENERGIZATION OF SAID WINDING, MEANS BIASING SAID ARMATURE TO ITS DE-ENERGIZED POSITION, CONTACT MEANS FOR CONTROLLING THE CURRENT TO SAID ARMATURE AND INCLUDING A FIXED CONTACT AND A MOVABLE CONTACT, A CONTACT CARRIER CARRYING SAID MOVABLE CONTACT AND BIASING SAID MOVABLE CONTACT OUT OF ENGAGEMENT WITH SAID FIXED CONTACT, A SECOND ARMATURE OF GENERALLY CHANNEL-SHAPE HAVING A PAIR OF LEGS INTERCONNECTED BY A BIGHT PORTION, SAID LEGS BEING CONNECTED TO SAID CONTACT CARRIER AND SAID ARMATURE BEING AXIALLY ALIGNED WITH SAID OPENING WITH ITS BIGHT PORTION INWARDLY RELATIVE TO SAID OPENING AT THE OTHER END OF SAID OPENING WITH RESPECT TO SAID FIRST ARMATURE FOR MOVEMENT BETWEEN AN ENERGIZED POSITION BIASING SAID CONTACTS INTO ENGAGEMENT AND A DE-ENERGIZED POSITION WITH SAID SECOND ARMATURE MOVED UPWARDLY OF SAID OPENING TO OPEN SAID CONTACTS IN RESPONSE TO THE ENERGIZATION AND DE-ENERGIZATION OF SAID WINDING, AND MEANS INTERCONNECTING SAID CONTACT CARRIER AND SAID FIRST ARMATURE FOR MOVING SAID MOVABLE CONTACT BETWEEN AN ENGAGED AND DISENGAGED POSITION RELATIVE TO SAID FIXED CONTACT IN RESPONSE TO THE DE-ENERGIZATION AND ENERGIZATION OF SAID WINDING.