US3216527A

US3216527A - Apparatus for changing crankcase oil

Info

Publication number: US3216527A
Application number: US255594A
Authority: US
Inventors: Oliver G Lewis
Original assignee: Exxon Research and Engineering Co
Current assignee: ExxonMobil Technology and Engineering Co
Priority date: 1963-02-01
Filing date: 1963-02-01
Publication date: 1965-11-09
Anticipated expiration: 1982-11-09
Also published as: GB1027250A

Description

Nov. 9, 1965 o. G. LEWIS APPARATUS FOR CHANGING CRANKCASE OIL 6 Sheets-Sheet l Filed Feb.

mDwE lill Oliver G. Lewis mvenfor By Cecil C. Schmid? Agen Nov. 9, 1965 o. G. L Ewxs APPARATUS FOR CHANGING CRANKGASE OIL 6 Sheets-Smet 2 Filed Feb.

@mommy @00 FIGURE 2 Oliver G. Lewis Inventor By Cecil c. Schmidt Agent Nov. 9,` 1965 o. G. LEWIS 3,216,527

APPARATUS FOR CHANGING CRANKCASE OIL Filed Feb. l, 1963 6 Sheets-Sheet 3 FIGURE 5 FIGURE 3 FIGURE 4 Oliver G. Lewis Inventor By Cecil C. Schmidt Agent Nov. 9, 1965 o. G. LEWIS APPARATUS FOR CHANGING GRANKCASE OIL 6 Sheets-Sheet 4 Filed Feb.

Oliver G. Lewis Inven'for By Cecil C. Schmidt Agent Nov. 9, 1965 o. G. LEWIS APPARATUS FOR CHANGING CRANKCASE OIL 6 Sheets-Sheet 5 Filed Feb.

[ I DRAIN ADD REFILL I L SWITCH 44 ANTITY SELECTOR 7 OIIver G. Lewis Inventor FIGURE By Cecil C. Schmidt Agent Nov. 9, 1965 o. G. I Ewxs 3,216,527

APPARATUS FOR CHANGING CRANKGASE OIL Filed Feb. l, 1965 6 Sheets-Sheet 6 DRAIN PB.

VACUUM PUMP BRIDGE RECTIFIER HO VOLT AC POWER SUPPLY Oliver G. Lewis invenor FIGURE 8 By Cecil C. Schmidt Agent United States Patent O 3,216,527 APPARATUS FoR CHAYGING CRANKCASE ouJ Oliver G. Lewis, Westfield, NJ., assigner to Esso Research and Engineering Company, a corporation of Delaware Filed Feb. l, 1963, Ser. No. 255,594 Claims. (Cl. 184--l.5)

This application is a continuation-in-part of my copending application Serial No. 230,868, now abandoned, -led October V16, 1962.

This invention relates to a method and apparatus for draining used lubricating oil from a lubricant holding case and for subsequently adding new oil to said case.

THE PROBLEM The conventional method for replacing used oil in the crankcase of an internal combustion engine mounted in a motor vehicle is to first drive the vehicle, eg., automobile, onto a hydraulic lift and elevate it to a height several feet above the ground. It is then necessary for a mechanic to crawl or walk under the automobile and remove the drain plug presently used to close the bottom of the crankcase. The oil is allowed to ilow from the crankcase into a suitable receptacle. The drain plug is then manually replaced and the automobile lowered. The cap on the crankcase ll pipe is removed and a pre-selected quantity and quality of new motor oil is manually added to the crankcase via the fill pipe. This conventional method for replacing used oil in the crankcase of an internal combustion engine has numerous disadvantages, including the requirement for a hydraulic lift or oil pit, the length of time required, the possibility of crossthreading the drain plug, the length of time that an operators presence is required, and the accompanying mess. More importantly, conventional draining techniques leave a sizable quantity of oil remaining in the crankcase. Because conventional draining is incomplete, sludge and foreign particles often remain in the crankcase.

Numerous attempts have been made to develop suitable devices for draining used oil from the crankcases of motor vehicles but none have been entirely successful.

These prior art devices, each an apparent advance in the art at their particular point in time, are represented by the following U.S. patents: Nos. 1,609,697; 1,659,019; 1,666,992; 1,815,221; 1,841,505; 1,886,098; 1,962,623; 2,105,761; 2,216,360; 2,206,992; 2,477,450; 2,552,749; 2,603,312; 2,612,289; and 2,635,550.

These previous attempts at oil removal suffered from various deficiencies. In some cases, the amount of equipment (and cost thereof) to be permanently attached to each automobile was prohibitive. Some devices were so complex that even though they had some definite advantages they were not commercially accepted because it was easier for the service station attendant to perform the old manual draining techniques. Still other devices were so bulky and expensive that they were not acceptable. Moreover, most of these devices only drained the oil and manual techniques still had to be employed to add new oil.

An added ditiiculty in developing a device to be used in commercial service stations is that automobile owners are ultra-conservative. They are so accustomed to the practice of having the used oil drained from their automobile engines through the drainage outlet in the Ibottom of the crankcase that the vast majority are skeptical of the ability of any device to effectively remove the used oil from the crankcase. Most customers want to know that the oil has been removed and they want to decide this fact for themselves. They normally will accept the word of a mechanic or the indication of a ma- 3,2i6,527 Patented Nov. 9, 1965 ICC chine, unless they can actually watch the oil removal being performed.

THE INVENTION A method and apparatus for overcoming many of the deficiencies of the prior art systems has now been discovered. The present invention involves broadly the method and apparatus for automatically withdrawing used oil from the crankcase of an internal combustion engine by suction and automatically adding new oil, under pressure, to the crankcase. The apparatus is designed so that the customer has a visual indication of the condition of the used oil which has been removed from his automobile. An additional feature of the present invention resides in the fact that the apparatus is further designed to give the customer a visual indication of the quantity and quality of the new oil which is to be added to the crankcase of his automobile. These two visual means are so located that the customer can visually compare the quantity and quality of the new and used oils. By electronicaily actuating the apparatus, the used oil can be withdrawn from the crankcase, new oil can be measured out, a visual comparison made by the customer between the new and the used oil, and the new oil can be automatically added to the crankcase. A feature of the present inl vention which is of consider-able importance is that the cycle of the `draining and filling operations, as well as the degree of drainage, is controlled by the Aapparatus and cannot be ,altered 4by the operator except through limited controls.

The present device is thought to be unique in that it is compact (much smaller than a conventional gasoline pump), easy to operate, is extremely fast, is not prohibitively expensive, is essentially trouble free, and requires the permanent installation of a very minor amount of inexpensive equipment on the motor vehicle itself. Moreover, these minor changes to the vehicle are easily incorporated during the original manufacturing process at a nominal cost.

The present invention will be more clearly understood by reference to the following detailed description taken in connection with the accompanying drawings in which:

FIGURE l is a block diagram of the electronic oil changer of the present invention,

FIGURE 2 is a right perspective View of an electronic oil changer constructed according to the teachings of the present invention,

FIGURE 3 is a side view of a connecting device which can be used to connect the flexible hose of the electronic oil changer to an oil evacuation tube,

FIGURE 4 is a front view, partly in section, of a crankcase having a drain plug type evacuation tube installed thereon,

FIGURE 5 is a front view, partly in section, of a crankcase having a Wall-type evacuation tube installed thereon,

FIGURE 6 is a diagrammatic view of the oil changer of the present invention and FIGURES 7 and 8, taken together, are a schematic diagram of the control system of a preferred embodiment of the present invention.

GENERAL DESCRIPTION AND OPERATION Referring now to FIGURE l, the hood of an automobile (not shown), for example, is raised and a flexible hose l, attached to the electronic oil changer, is then placed in communication with the lower reaches of the automobile crankcase in a manner as will be later described. The service station attendant then selects the quantity and quality of the new oil to be charged into the engine. This is done through dials located on the control panel (not shown) of the electronic oil changer. The attendant may then, for example, depress a button (not shown) on the electronic oil changer marked automatic In the electronic oil changer, a vacuum is produced in the transparent used oil cylinder 3 by some convenient means (e.g., electric vacu'um pump 2). This vacuum draws the used oil from the crankcase (not shown) through flexible hose 1 into the transparent used oil cylinder 3 where the customer may see it. Meanwhile, the previously selected quality and quantity of new oil is being automatically metered by an automatic metering device 4 (e.g., constant displacement cylinder) into a second transparent cylinder (new oil cylinder 5) where the customer may make a direct comparison between the sparkling new oil and his dirty used oil. It should be realized that once the oil quality, e.g., oil quality #3, has been selected only its corresponding metering device 4 will be in operation. The metering devices related to the other oil qualities will be idle. The quantity metered out by the automatic metering device 4 may be in increments of one pint or less if desired.

By the term vacuum as used throughout this specification, it is intended that zero inches of Hg will correspond to no vacuum at all (normal atmospheric pressure) and that a vacuum of 29.92 inches of Hg corresponds to a perfect vacuum, i.e., zero p.s.i.a. Thus a reduction in vacuum is intended to denote an increase in absolute pressure.

As the major portion of the used oil is drawn from the crankcase (not shown) by the vacuum, air is drawn into the used oil cylinder 3 from the crankcase and rapidly reduces the vacuum within used oil cylinder 3. This sudden burst of air from the crankcase through flexible hose 1 into used oil cylinder 3 is effective in removing bits of foreign materials from the crankcase, e.g., sand, metal chips, etc. As the vacuum drops to a predetermined level of from 2 to 12 inches Hg, e.g., 4 to 10 inches Hg, a timing cycle starts and allows a number of seconds, usually from to 60 seconds, e.g., l5 to 30 seconds, of continued pumping to collect the remaining oil from the crankcase. It is to be noted that this timing cycle does not start until the major portion of the used oil has been withdrawn from the crankcase and the nal volume of used oil remaining in the crankcase is not, therefore, dependent on the temperature and viscosity of the oil or the total quantity of oil torbe removed. As soon as the timed cycle has been completed, thus indicating the oil removal cycle to be complete, the electronic oil changer will automatically cause the new oil to be forced from the new oil cylinder 5 into the'crankcase via the flexible hose 1 without further attention from the operator. This addition of new oil to the crankcase is done by means of air pressure from source 6. Suitable valves will prevent the entry of new oil into used oil cylinder 3. After the new oil has been delivered to the crankcase, the system will automatically eliminate the used oil from used oil cylinder 3 into a suitable receptacle (slop oil tank 7) by means of air pressure from source 6 and then shut off. Indicator lights may be mounted on the electronic oil changer to show the customer the quantity and quality of oil charged to the engine.

VIf desired, the electronic oil changer may be set, e.g., by dialing zero quantity of new oil, to remove used oil and then stop after the used oil has been removed. At this point new oil may be selected and added to the crankcase or, if desired, the used oil may be returned to the engine merely by pressing a Refill button on the control panel.

FIGURE 2 is a right perspective view of a portable electronic oil changer that has been constructed according to the present invention. The cabinet 8 houses the necessary relays, vacuum pump, constant displacement pumps for' metering new oil, wiring, etc. Transparent cylinders 3 an-d 5 are employed for used oil and new -oil respectively and may have a capacity of from 6 to 12 quarts or more. Use of these cylinders is contemplated where individual customer appeal is required. When captive customers are encountered (taxi fleets, etc.) they are not needed. The control switches 9 are used to signal the electronic oil changer to drain the used oil, to add new oil, to rell the crankcase with the used oil that has been previously withdrawn, to operate automatically, or to reset the entire apparatus. Dial 10 is used to select the quality of the new oil, i.e., grade of oil, and dial 11 is used to select the quantity of new oil to be measured out into new oil cylinder 5 prior to being added to the crankcase. Pressure gage 12 indicates the pressure, e.g., air pressure, used to force the new oil into the crankcase from new oil cylinder 5 during the filling operation. This pressure will usually be from 2O to 100 p.s.i.g., although other pressures may be used, eg., 40 to 80 p.s.i.g. Pressure gage 13 indicates the pressure used to feed the quality grade of new oil selected to its associated constant displacement metering device or pump 4 (not shown) which meters the selected grade of new oil with a high degree of precision. This oil feed pressure may range from 20 to l0() p.s.i.g., although pressures of 40 to 8O p.s.i.g. are most frequent. Vacuum gauge 14 indicates the vacuum applied to used oil cylinder 3 in drawing the used oil from the crankcase The vacuum will usually be from 20 to 29 inches Hg, e.g., 24 to 28 inches Hg. A bank of lights 15 may be used to indicate to the customer and/or operator the quantity of new oil that has been added to new oil cylinder 5 (e.g., one light may be illuminated per each one pint increment of new oil). Additionally,

transparent cylinders

3 and 5, when used, may be graduated. Flexible hose 1 of some convenient length, eg., 3 to l0 feet, and of an internal diameter of from about 1A" to 1/2, e.g., about 3%", is connected to an internal manifold (not shown) within the electronic oil changer which is, in turn, connected to

transparent cylinders

3 and 5. At the free end of the flexible hose 1 is a connector 16 of the type shown in FIG- URE 3. This connector should be of the quick-connect type and capable of withstanding the pressure of new oil being forced into the crankcase, as well as withstanding the vacuum during oil withdrawal. This connector 16 is used to connect exible hose 1 to an evacuation tube mounted in or on the crankcase. When, however, used oil is to be withdrawn from a crankcase Via the oil ll pipe or the oil measuring stick guide tube, the connector 16 can be used to connect exible hose 1 to a tube or wand that has been inserted into one of those openings. Preferably, the evacuation tubes as hereinafter described are employed. Input tubes 17 and 18 are used to feed the new and used oil into

cylinders

3 and 5 and may contain check Valves to prevent back ow or contamination between different qualities of oil.

-FIGURE 3 illustrates in detail a connecting device (e.g., connector 16 of FIGURE 2) which can be used to rapidly join the flexible hose 1 of the electronic oil changer to the upper end of an evacuation tube, wand, etc. A connector of the type shown is manufactured by Mechanical Products Corporation, 1716 West Hubbard Street, Chicago 22, Illinois. In operation, lever 16a is depressed and the end of an evacuation tube, wand, etc., is inserted into the open end of connector 16. Lever 16a is then released and a leak-free connection is formed.

FIGURE 4 illustrates a drain plug-type evacuation tube which can be used with present day automobiles in cooperation with the present invention. The plug 19, itself, resembles a normal drain plug and its threaded end is hollow (19a) for part of its length in an axial direction. It is provided with one or more lateralports 19b. It is passed through an annular member 20 (e.g., made of nylon, etc.) and screwed into the normal drainage outlet of crankcase 21. Thus, oil contained in the crankcase 21 can, under the influence of the automatic oil changer, flow down through the hollow portion 19a of plug 19, out the lateral ports 1911, through annular member 26 and on to the oil changer (not shown in this view) via tube 23 as shown by the arrows. During oil changing operations, the flexible hose 1 of the oil changer would be connected to tube 23 by means of a connecting device, eg., connector 16. Generally tube 23 will have an inside diameter of about 1A to 1./z, although thin walled S/" tubing is preferred. At the present time, it is believed that ve sizes of drain plugs will accommodate all mass produced American cars since 1950, with the possible exception of the Hudson.

FIGURE 5 illustrates a wall-type evacuation tube as it might appear if it were part of the manufacturers installed equipment. An opening is cut in the wall of crankcase 21 and a rigid tube 26 is inserted therethrough. Tube 26 will generally have an inside diameter of about 1A to 1/2 inch although use of thin walled (e.g., 0.040 or less) 3/s inch O.D. tubing is preferred. One end of tube 26 rests on the oor of crankcase 21 at its lowest point. The lower end of tube 26 is contoured to rest against the bottom of crankcase 21 at its lowest point. The contoured end of dip leg 26 is notched to provide a lateral area open to the oil which is approximately equal to the inside cross-sectional area of tube 26. Preferably, the maximum height of the notches 25a in the end of tube 26, above the floor of crankcase 21', will be no more than 0.15 inch and preferably not less than 0.080 inch. This allows substantially all of the oil held in crankcase 21' to be withdrawn by suction created in tube 26. Tube 26 is aiiixed to the wall of crankcase 21' at point 25 by some suitable technique, e.g., welding. One end of a ilexible tube 23' is attached to the uppermost end of tube 26 and the other end is eX- tended to a point above the normal oil level 22 in crankcase 21. When not in use, tube 23' may be closed by some suitable device 24, eg., a plastic snap cap.

According to the present invention, an evacuation tube, such as one of those shown in FIGURES 4 or 5, is attached to a lubricant containing case 21, e.g., a crankcase. The exible hose portion (e.g., 23 or 23) of the evacuation tube is extended into the upper engine compartment, terminating at a point well above the normal oil level 22 within the crankcase 21.

By far the most satisfactory method for removing used oil is through the wall-type evacuation tube as shown in FIGURE 5. Alternatively, however, the other types of evacuation tubes may be used and, in some instances, oil may be withdrawn via a flexible hose or wand inserted into the oil fill pipe or oil measuring stick guide tube.

DETAILED DESCRIPTION AND OPERATION The detailed description and sequence of operation which follows is made with specific reference to FIG-

URES

6, 7, and 8 which should be read simultaneously.

FIGURE 6 is a diagrammatic view of a preferred embodiment of the present invention while FIGURES 7 and 8, taken together, are a schematic diagram of a control system for such `an oil changer. For ease in reading the iigures, the following reference symbols have been used.

L-line LLS-lower limit switch M-micro P-pressure PB-push button RL-relay SV-solenoid valve SVV-switch TD-time delay ULS-upper limit switch V-vacuum The several hourglass shaped contacts shown in vertical alignment above each element, eg., relay of FIGURE 7, correspond to the electrical contacts of their related element. For example, three (3) contacts are shown (by the dotted line), which also indicates that the contacts are ganged, to correspond to relay 35. The upper Contact is shown in a normally open position (as regards the circuit); the center contact is shown in a normally closed position (as regards the circuit) and the lower contact is not being used at all. The black portion of the hour-glass shaped contacts thus represents the conductive position while the White portion represents the non-conductive position. Once a relay is energized, the black and white portions will reverse themselves. Three contacts have been shown for all relays since many commercially available relays have that number of contacts. In accordance with conventional electrical drawing practice, FIGS. 7 and 8 show the contact positions of each of the relays in the power oif or uncnergized state. It will be understood that when in the normal sequence of operation a relay or push button, etc. is actuated, its associated contacts will all transfer from the electrical state shown in FIGS. 7 and 8 to an opposite electrical state. It will also be understood that this transfer of electrical state is effected by the simultaneous transfer of all three central moving contacts of each relay from their indicated position in electrical contact with the lower black normally closed contact into contact with the upper white normally open Contact.

It is assumed, in the following description, that the hose 1 of the electronic oil changer of FIGURE 6 has been suitably connected to the lower reaches of a crankcase of a motor vehicle.

NORMAL SEQUENCE (l) Select the desired quantity and quality of new oil to be added to new `oil cylinder 5. This selection is made by means of quantity selector switch l1 and quality selector switch 10. The selection of oil quality, e.g., a premium grade motor oil, through quality selector switch 10 will activate the corresponding oil metering device 4 (e.g., constant displacement cylinder) with its attendant oil control solenoid valve 4t), control valve 43, and upper and

lower limit switches

38 and 42, respectively. Thus if the quality of new oil selected by quality selector switch 10 was that represented by the extreme left postion shown in FIG. 8, only one set of upper and lower limit switches (38 and 42) would be employed and all the remaining upper and lower limit switches ULS 3S and LLS 42 and their associated solenoid valves SV 4G shown in brackets would be idle. Metering stepping switch Mis used to cause the measurement of new oil to be halted when the selected quantity of new oil has been added to new oil cylinder 5.

(2) Press automatic push button switch 27 to close its normally open contact points.

(3) Relay 2S and time delay relay 29 are thus placed in parallel across lines L-36 and L-73 and energized and latched (i.e., maintained energized) through the uppermost set of normally closed holding points of relay 30 (reset relay) until such later time that relay 30 is energized.

(4) The operation of push button switch 27 is also eiectlve to connect the hot side (L-36) of the power supply to the vacuum pump 2 and solenoid valve 31 which are energized via the normally closed lowerrnost contact on RL-32. Once the push button 27 is released the pump 2 and valve 31 remain connected to the line L-36 through the normallly open uppermost contacts of relay 28 and the normally closed uppermost contact points lon relay 30.

(5) Three-way valve 33 is in position A so that used ci il csoming through line 1 will be fed into used oil cylin- (6) Relay 34 is energized through relay 35 and is latched to line 36.

(7) Solenoid valve 31 opens to allow the vacuum to be applied to used oil cylinder 3 and vacuum switch 37.

(8) The normally open Contact on time delay 29 allows vacuum switch 37 to build up vacuum and open its contact.

(9) The circuit through the upper limit switch 38 activates relay 39 and solenoid valve 40. Solenoid valve 40 remains locked into position until oil pressure on top of measuring piston 41 forces the measuring piston 41 downward and trips lower limit switch 42 releasing relay 39 and closing solenoid valve 40.

(10) When solenoid valve 40 is closed, the ow of new oil through control valve 43 is changed and the new oil then flows up against the bottom of measuring piston 41 forcing it upward against upper limit switch 38. This causes the discrete quantity of oil above measuring piston 41 to be forced out into new oil cylinder 5.

(l1) If the quantity of new oil required by quantity selector switch 11 (as modied by metering stepping switch 44) has not been satisfied, upper limit switch 38 will continue to yclose the circuit to re-energize relay 39 and solenoid valve 40 and steps 9 and 10 supra will be repeated until the desired quantity of o'il has been provided.

(l2) When the quantity selected by quantity selector switch 11 has been satisfied, the circuit through upper limit switch 38 and selector switch 11 will energize relay 35, deenergizing relay 39 and solenoid valve 40 will remainv closed.

(13) As the major portion of the used oil is drawn from the crankcase Via line 1 through valve 33 into used oil cylinder 3, air, from the crankcase, entering used oil cylinder 3 will cause the vacuum to reduce (increase in pressure).

(14) As the vacuum drops to 6 inches of mercury, Vacuum switch 37 closes and activates time delay 45 through relay 46.

(15) Time delay 45 allows the vacuum pump 2 to continue pumping for seconds to remove the last of the used oil from the crankcase and to clear hose 1.

' (16) As time delay 45 times out, it will act through relay 35 and energize relay 32, time delay 47, solenoid valve 48, and solenoid valve 49.

(17) Activation of relay 32 stops vacuum pump 2, deenergizes solenoid Valve 31, and completes the D C. circuit to energize relay 50. Time delay 45, acting through relay 28, latches in relay 51.

(18) Valve motor 52 is energized by relay 50 and turns cam 53 until micro switch 54 is Iopened and drops out relay 50 with valve 33 is position B, thus connecting the crankcase to new oil cylinder 5 via line 1.

(19) As micro switch 54 is opened solenoid valve 48, solenoid valve 49, relay 32 and time delay 47 will be energized since the oil measuring device 4 has completed its metering job `and metering stepping switch 44 has completed its sequence. This connects the line air pressure 6 (e.g., 30 p.s.i.g.) to the top of the new oil in the new oil cylinder 5 and forces the previously measured new oil from cylinder through valve 33 and line 1 into the crankcase. (20)V Time` delay 47 prevents the action of pressure switch 55 until the pressure builds up within new oil cylinder 5. Pressure switch 55 opens before the time out of time delay 47.

(21) As all of the new oil within cylinder 5 is discharged, the pressure within the cylinder will fall. When the pressure reaches 5 p.s.i.g., time delay 47 and the closing of the contact on pressure switch 55 will activate relay 30 which drops out relay 51 and latches in relay 56.

(22) Relay 56 will then activate valve motor 52, which turns cam 53 causing micro switch 57 to open (with Valve 33 in position A).

(23) The metering stepping switch 44 is energized through relay 56 and resets for the next cycle. When the metering stepping switch reaches home, it drops out relay 35 which drops out relay 32,

defenergizing solenoid valves

48 and 49.

RETURNING USED OIL TO THE `CRANKCASE (l) Press refill push button switch 58.

(2) Relay 59 will be energized and latch in through micro switch 69. The Valve motor 52 will be energized and turn cam 53 until micro switch 60 is opened, dropping out relay 59 with valve 33 in position C.

(3) Relay 61 will be energized

opening solenoid valves

62 and 63. Solenoid valve 64 and time delay 65 are also energized through relay 61.

(4) Line air introduced into used oil cylinder 3 through solenoid valve 62 will force the used oil through solenoid valve 63 to valve 33 which is in position C and on to the crankcase Via line 1.

(5) As the pressure in used oil cylinder 3 drops to 5 p.s.i.g. (due to all of the oil being discharged) pressure switch 66 acting through time delay 65 will energize the reset relay 39. Reset relay 30 drops out relay 51 and latches in relay 56.

(6) Valve motor 52 is energized by relay 56, turns cam 53, causing micro switch 57 to open with valve 33 in position A. Metering stepping switch 44 is energized through relay 56 and resets for the neXt cycle. When the metering stepping switch 44 reaches home, it `drops out relay 32 de-energizing

solenoid valves

48 and 49.

ADDING NEW OIL WITHOUT FIRST DRAINING USED OIL (l) Select the quantity and quality of oil by means of switches 10 and 11.

(2) Press the add oil push button switch 67.

(3) Relay 51 is latched in. Relay 34 is energized and latches through relay 35 to L-36. y

(4) Relay 34 activates relay 39 and solenoid valve 40 through upper limit switch 38. Solenoid valve 40 remains in position until the oil pressure on top of measuring piston 41 forces the measuring piston 41 downward and trips lower limit switch 42 releasing relay 39 and closing solenoid valve 40.

(5) When solenoid valve 40 is closed, the flow of new oil through control valve 43 is changed and the new oil then flows up against the bottom of measuring piston 41 forcing it upwardly against upper limit switch 38 This causes the discrete quantity of oil above measuring piston 41 to be forced out into new oil cylinder 5.

(6) If the quantity of new oil required by quantity selector switch 11 has not been satisii'ed, upper limit switch 38 will continue to close the circuit and

steps

4 and 5, supra, will be repeated until the desired quantity of new oil has been provided.

(7) When the quantity of oil selected by quantity selector switch 11 has been satisfied, the stepping switch 44 closes the circuit through relay 34, metering stepping switch 44, quantity selector 11 and relay 46, thus stopping the measuring sequence and latching in relay 35.

(8) Relay 35 energizes relay 32, time delay 47, and

solenoid valves

48 and 49.

(9) Activation of relay 32 energizes valve motor 52 through relay 5 0. Valve motor 52 turns cam 53 until mioroswitch 54 is opened and relay 50 drops out with valve 33 in position B.

Y (10) Air enters new oil cylinder 5 through solenoid valve 48. The new oil is then forced from new oil cylinder 5 to the crankcase via line 1 in the manner as previously described with reference to the Normal Sequence.

(lil) As the new oil is discharged from new oil cylinder 5, the pressure within the cylinder will drop. When the pressure reaches 5 p.s.i.g. time delay 47 and pressure switch 55 will activate relay '30, dropping out relay 5'1 and latching in relay 56.

(12) Valve motor 52 will be energized by relay 56 and turn cam 53 until microswitch 57 is opened with valve 33 in position A. The metering stepping switch 44 is energized through relay 56 and resets for the next cycle. As the stepping switch 44 reaches home it drops out relay 35 which drops out relay 32 thus de-energizing

solenoid valves

48 and 49.

Used oil is drained from used oil cylinder 3 by pressing the drain push button switch 68 which allows the line air pressure to enter the top of used oil cylinder 3 and force the used oil through solenoid valve 64 to slop oil 7. Reset push button switch 69 is used to reset the electronic .29 changer, at any point in its operation, to its initial static position. The various rectiiiers (7G and 71) resistor 72 and capacitor 73 are used to provide the necessary electrical requirements for the sundry relays, motors, etc. More specically, rectifier 7l supplies D.C. power for the D.C. relays and metering stepping switch 44. Rectifier 70 is a gating mechanism to allow D.C. relay 56 to only latch in when a positive pulse is received. Relay 30, on the same circuit, will latch in on either a positive or negative pulse. Resistor 72 and capacitor 73 form a time constant to temporarily latch in relay Si) until it is latehed in by microswitch 54. It then olers no further holding power.

EXAMPLES The present invention will be more clearly understood by reference to the following examples which include a preferred embodiment.

Example 1 A completely self-contained apparatus substantially as described has been constructed for experimental purposes and tested on a number of automobiles on which evacuation tubes of the types shown in FIGURES 4 and 5 had been mounted. In the device, as constructed, an initial vacuum of 27 inches Hg was employed for draining the used oil and a 20 second time cycle was set to begin when the vacuum had diminished to 7 inches Hg. A pressure of 60 p.s.i.g. was used in introducing the new oil to the constant displacement cylinder 4 used for metering the new oil into the new oil cylinder 5. Air pressure of 30 p.s.i.g. was applied to force the new oil from the new oil cylinder into the crankcase 21. It was found that, with a thin walled evacuation tube having a 3/8 inch outside diameter, used oil (at 125 F.) could be removed at the rate of l lpint in every 51/2 seconds. It was found that the hood of an automobile could be raised, the ilexible hose 1 from the electronic oil changer connected to the evacuation tube, the quantity and quality of new oil selected, 4 quarts of used oil removed from the crankcase 21 and 4 quarts of new oil added to the crankcase 21 in just l under 2 minutes.

Numerous tests were conducted using the apparatus just described and it was determined that the oil removal via this electronic oil changer would, in all tested cases, equal or exceed the extent of oil removal via the normal drain plug technique. Typical quantities of residual used oil found in crankcases after evacuation with the electronic oil changer when used in conjunction with an evacuation tube of the type shown in FIGURE 5 were on the order of 5 cc. In most automobiles it was possible to exceed the oil removal possible through conventional draining by from 100 to 60() cc. An example of such a situation was found in a 1959 Lincoln where the drain plug is located part way up the side of the craukcase, thus allowing approximately 570 cc. of oil to remain in the crankcase after conventional draining. By installing the wall-type evacuation tube as shown in FIGURE 5 and using the electronic oil changer, it was possible to reduce this quantity of residual oil to about 5 cc. Using the drain plug type evacuation tube of FIGURE 4, the oil removal is substantially the same as that obtained by conventional draining` Example 2 For purposes of experimentation and testing, an industrial model of the electronic oil changer has also been constructed for use on taxi fleets, trucks, etc., where there is no induw'dual customer to satisfy. Here, the equipment was modified to eliminate

transparent cylinders

3 and 5. The used oil was pumped directly to a slop tank 7 and a single grade of new oil was used. Multiple grades of new oil were also tested using several constant displacement cylinders 4. The results produced by that industrial oil changer were essentially the same as these obtained with the portable model described in Example l.

l0 The selection of commercially available counterparts of the various components used in constructing the aforementioned oil changers are believed to be well within the skill of the art. However, for whatever benefit that the public may derive, the following fragmentary list of suitable components is provided.

Stepping switch-Clare type 20 NBR R1858 Push buttons-Honeywell Series 2 Selector switch-JET #MS-ZO-Z Rectitier-Full wave, l amp, 115 v. D.C.

Relays-Potter & Bromeld KRP Time delays-Amperite Selector switch-Centralab Resistor-47K ohms Capacitor-12 UF 150 v.

Glass cylinders (2)-Pyrex Double Tough 6 x 18" Vacuum pump-Gast #0740-V4-Gl80X Solenoid valve-3 way diff. Skinner V54DB2075 Solenoid valve2 way Skinner LC2DB3150 Vacuum switchMeletron DIT-H18 Gauge- -15-0100# U.S. 17055 Pressure switch-Hobbs M1925 Check valve-Circle Seal #530B 2M-0.5

Measuring cylinder-Allen Air #A400-4.825

Gauge-O-# U.S. FIGURE 644 Cam-1A alum. plate Motor- New England gear, 5 rpm., 66 inch, 16 torque,

Model HD1 Tubing connector-Mechanical Products TC-1304 DISCUSSION The vacuum type of apparatus as has just been described has a decided advantage over the use of positive displacement pumps for oil removal. For example, it has been noted that, in new cars, sand from the various castings will appear in the oil during the rst tWoor three oil changes. Oil changers utilizing positive displacement pumps have been employed on new cars and found to be ineffective after 35 to 50 oil changes due to the extensive wear caused by this loose sand and foreign material. No such problems are encountered when using the present equipment which has been exhaustively tested.

The electronic oil changer may be constructed as a portable mechanism or as a permanent part of the gasoline dispensing island iixtures. As a permanent installation, only the relay cabinet, metering devices for the new oil and the transparent cylinders need be mounted at the island. The vacuum source, new oil in bulk, and the slop oil tank could be located in some central location and piped to the various islands.

Having thus described the present invention with a ce-rtain degree of particularity, it is to be realized that numerous other modifications and adaptations (e.g., using the .device to remove fuel from fuel tanks, flushing, etc.) can be made within the spirit and scope of the invention as hereinafter claimed.

I claim:

1. A sequential switching device suitable for use as automatic control means in an apparatus for withdrawing used oil from a lubricant holding case by vacuum and thereafter adding new oil under pressure to said case, wherein said apparatus includes conduit means, distributing means in communication with said conduit means, vacuum means in communication with said distributing means, oil supply means in communication with said distributing means, air pressure means cooperating with said oil supply means, and automatic control means for said vacuum means, said air pressure means, said oil supply means, and said distributing means, which comprises in combination (a) initiator means for activating said vacuum means to thereby create a vacuum,

(b) a first means responsive to said initiator means for establishing communication between said lubricant holding case and said vacuum means through l l said conduit means and said distributing' means, said vacuum thereby withdrawing used oil from said lubricant holding case,

(c) a second means responsive to the level of vacuum produced by said vacuum means, said second means deactivating said vacuum means after said vacuum reaches a predetermined level,

(d) selector means for selecting a discrete quantity of new oil,

(e) a third means responsive to actuation of said selector means for measuring said discrete quantity of new oil,

(f) a fourth means responsive to the deactivation of said vacuum means for discontinuing said communication between said lubricant holding case and said .vacuum means, said fourth means causing said distributing means to establish communication between said lubricant holding case and said oil supply means, said oil supply means including said measured quantity of new oil,

(g) a fifth means responsive to said deactivation of said vacuum means and responsive to said third means, said lifth means operatively connecting said air pressure means with said oil supply means including said measured quantity of new oil, thereby forcing said new oil into said lubricant holding case,

(h) a sixth means responsive to the level of pressure produced by said air pressure means, said sixth means disconnecting said air pressure means from said oil supply means after said pressure reaches a predetermined level,

(i) a seventh means responsive to said sixth means for resetting said sequential switching device to a normal position.

2. A sequential switching device as defined in claim 1 which also includes an eighth means selectively cooperating with said seventh means for resetting said sequential switching device to said normal position.

3. A sequential device as defined in claim 1 which also includes a ninth means selectively cooperating with said fourth and fth means to eiiectuate the addition of said measured quantity of new oil, said ninth means bypassing said initiator means, thereby eliminating the sequence of operations relating to said withdrawal of used oil.

4. A sequential switching device suitable for use as automatic control means in an apparatus for withdrawing used oil from a lubricant holding case by vacuum and thereafteraddingA new oil under pressure to said case, wherein said apparatus includes conduit means, distributing means in communication with said conduit means, vacuum means in communication with said distributing means, oil supply means in communication with said distributing means, air pressure means cooperating with said oil supply means, and automatic control means for said vacuum means, said air pressure means, said oil supply means, and said distributing means, which comprises in combination (a) initiator means for activating said vacuum means to thereby create a vacuum,

(b) a rst means responsive to said initiator means for establishing communication between said lubricant holding case and said vacuum means through said conduit means and said distributing means, said vacuum thereby withdrawing used oil from said lubricant holding case,

- (c) a second means responsive to the level of vacuum produced by said vacuum means, said second means deactivating said vacuum means after said vacuum reaches a predetermined level,

(d) selector means for selecting a discrete quantity of new oil,

(e) a third means responsive to said selector means Y for Vmeasuring said discrete quantity of new oil,

(f) a fourth means responsive to the deactivation of said vacuum means for discontinuing said communication between .said lubricant holding case and said vacuum means, said fourth means causing said distributing means to establish communication between said lubricant holding case and said oil supply means, said oil supply means including said measured quantity of new oil,

(g) a fth means responsive to said deactivation of said vacuum means and responsive to said third means, said ifth means operatively connecting said air pressure means with said oil supply means including said measured quantity of new oil, thereby forcing said new oil into said lubricant holding case,

(i) a seventh means responsive to said sixth means for resetting said sequential switching device to a normal position,

(j) an eighth means selectively cooperating with said seventh means for resetting said sequential switching device to said normal position, and

(k) a ninth means selectively cooperating with said fourth and fth means to effectuate the addition of said measured quantity of new oil, said ninth means bypassing said initiator means, thereby eliminating the sequence of operations relating to said withdrawl of used oil.

5. An electronic oil changer for withdrawing used oil from a lubricant holding case by vacuum and thereafter adding new oil by air pressure means to said case which comprises in combination:

(a) conduit means,

(b) distributing means in communication with said conduit means,

(c) vacuum means in communication with said distributing means,

(d) oil supply means in communication with said distributing means,

(e) initiator means for activating said vacuum means to thereby create a vacuum,

(f) a iirst means responsive to said initiator means for establishing communication between said lubricant holding case and said vacuum means through said conduit means and said distributing means, said vacuum thereby withdrawing used oil from said lubricant holding case,

(g) a second means responsive to the level of vacuum produced by said vacuum means, said second means deactivating said vacuum means after said vacuum reaches a predetermined level,

(h) selector means for selecting a discrete quantity of new oil,

(i) a third means responsive to said selector means for measuring said discrete quantity of new oil,

(j) a fourth means responsive to the deactivation of said vacuum means for discontinuing said communication between said lubricant holding case and said vacuum means, said fourth means causing said distributing means to establish communication between said lubricant holding case and said oil supply means, said oil supply means including said measured quantity of new oil,

(k) a iifth means responsive to said deactivation of said vacuum means and responsive to said third means, said iifth means operatively connecting said air pressure means with said oil supply means including said measured quantity of new oil, thereby forcing said new oil into said lubricant holding case,

(l) a sixth means responsive to the level of pressure produced by said air pressure means, said sixth means disconnecting said air pressure means from said oil supply' means after said pressure reaches a predetermined level,

(m) a seventh means responsive to said six-th means for resetting said sequential switching device to a normal position,

(n) an eighth means selectively cooperating with said seventh means for resetting said sequential switching device to said normal position, and

(o) a ninth means selectively cooperating with said fourth and fth means to effectuate the addition of said measured quantity of new oil, said ninth means bypassing said initiator means, thereby eliminating the sequence of operations relating to said With.

drawal of used oil.

14 References Cited by the Examiner UNITED STATES PATENTS 1,815,221 7/31 Sweetland 1841.5 5 2,320,048 5/43 Parson 184-15 FOREIGN PATENTS 707,315 4/54 Great Britain.

10 LAVERNE D. GEIGER, Primary Examiner.

MILTON KAUFMAN, Examiner.

Claims

1. A SEQUENTIAL SWITCHING DEVICE SUITABLE FOR USE AS AUTOMATIC CONTROL MEANS IN AN APPARATUS FOR WITHDRAWING USED OIL FROM A LUBRICANT HOLDING CASE BY VACUUM AND THEREAFTER ADDING NEW OIL UNDER PRESSURE TO SAID CASE, WHEREIN SAID APPARATUS INCLUDES CONDUIT MEANS, DISTRIBUTING MEANS IN COMMUNICATION WITH SAID CONDUIT MEANS, VACUUM MEANS IN COMMUNICATION WITH SAID DISTRIBUTING MEANS, OIL SUPPLY MEANS IN COMMUNICATION WITH SAID DISTRIBUTING MEANS, AIR PRESSURE MEANS COOPERATING WITH SAID OIL SUPPLY MEANS, AND AUTOMATIC CONTROL MEANS FOR SAID VACCUUM MEANS, SAID AIR PRESSURE MEANS, SAID OIL SUPPLY MEANS, AND SAID DISTRIBUTING MEANS, WHICH COMPRISES IN COMBINATION (A) INITIATOR MEANS FOR ACTIVATING SAID VACUUM MEANS TO THEREBY CREATE A VACUUM, (B) A FIRST MEANS RESPONSIVE TO SAID INITIATOR MEANS FOR ESTABLISHING COMMUNICATION BETWEEN SAID LUBRICANT HOLDING CASE AND SAID VACUUM MEANS THROUGH SAID CONDUIT MEANS AND SAID DISTRIBUTING MEANS, SAID VACUUM THEREBY WITHDRAWING USED OIL FROM SAID LUBRICANT HOLDING CASE, (C) A SECOND MEANS RESPONSIVE TO THE LEVEL OF VACUUM PRODUCED BY SAID VACUUM MEANS, SAID SECOND MEANS DEACTIVATING SAID VACUUM MEANS AFTER SAID VACUUM REACHES A PREDETERMINED LEVEL, (D) SELECTOR MEANS FOR SELECTING A DISCRETE QUANTITY OF NEW OIL, (E) A THIRD MEANS RESPONSIVE TO ACTUATION OF SAID SELECTOR MEANS FOR MEASURING SAID DISCRETE QUANTITY OF NEW OIL, (F) A FOURTH MEANS RESPONSIVE TO THE DEACTIVATION OF SAID VACUUM MEANS FOR DISCONTINUING SAID COMMUNICATION BETWEEN SAID LUBRICANT HOLDING CASE AND SAID VACUUM MEANS, SAID FOURTH MEANS CAUSING SAID DISTRIBUTING MEANS TO ESTABLISH COMMUNICATION BETWEEN SAID LUBRICANT HOLDING CASE AND SAID OIL SUPPLY MEANS, SAID OIL SUPPLY MEANS INCLUDING SAID MEASURED QUANTITY OF NEW OIL, (G) A FIFTH MEANS RESPONSIVE TO SAID DEACTIVATION OF SAID VACUUM MEANS AND RESPONSIVE TO SAID THIRD MEANS, SAID FIFTH MEANS OPERATIVELY CONNECTING SAID AIR PRESSURE MEANS WITH SAID OIL SUPPLY MEANS INCLUDING SAID MEASURED QUANTITY OF NEW OIL, THEREBY FORCING SAID NEW OIL INTO SAID LUBRICANT HOLDING CASE, (H) A SIXTH MEANS RESPONSIVE TO THE LEVEL OF PRESSURE PRODUCED BY SAID AIR PRESSURE MEANS, SAID SIXTH MEANS DISCONNECTING SAID AIR PRESSURE MEANS FROM SAID OIL SUPPLY MEANS AFTER SAID PRESSURE REACHES A PREDETERMINED LEVEL, (I) A SEVENTH MEANS RESPONSIVE TO SAID SIXTH MEANS FOR RESETTING SAID SEQUENTIAL SWITCHING DEVICE TO A NORMAL POSITION.