MXPA00011709A - Plenum oil seal - Google Patents

Abstract

An oil seal for a locking differential mechanism. The seal assembly includes a generally flat plate with a first generally circular oil seal adjacent an outer margin of the flat plate, a circular inner margin defining an opening in the flat plate with a second oil seal surrounding the inner margin, an oil outlet opening lying in an otherwise imperforate area between the first and second margins, and a cover for the flat plate with the cover and plate defining between them a passage for oil extending from a point radially outside the first seal to at least a point adjacent the oil outlet. The seal takes in a supply of oil from the differential sump and supplies it to a multi-plate clutch which is activated only when two axlesundergo rotation relative to each other and thereby actuate a gerotor type oil pump.

Description

"OVERPRESSURE OIL SEAL" BACKGROUND OF THE INVENTION The present invention relates generally to oil seals and, more particularly, to a combination of seal and acire steering device. Still further, the invention relates to a device that allows the oil, including a relatively thick oil, to be collected from a sump and supplied to a pump that operates only intermittently, and serves to supply pressure to an annular piston. The piston, in turn, when energized, acts through a multi-plate clutch and tends to block the satellite gears of a differential against relative rotation and thus locks the driving axles of a vehicle together. When there is little or no relative movement between the axes, the pump stops operating transiently and the axes are unlocked1. The seal also works to supply enough oil to allow somewhat limited sliding of the two shafts. The invention preferably includes a large punching, a small circular punching, and a third punching auxiliary serving, in cooperation with the main punching, to form a dip tube to supply the oil from the sump to the oil pump, when it performs the functions described above. In a preferred form, the main die includes one or more tabs to prevent rotation relative to the ring gear with which it is associated during use. Normally, the ring gear rotates and the seal steering device does not. Here, even though the overpressure seal of the invention has the function of oil direction and other functions, it is sometimes referred to herein, for convenience reasons, only as a "seal". In accordance with the invention, a? Preferred form of the device includes a part facing the intake of the oil pump, with a seal band extending around the outside thereof, and an opening of a smaller diameter closer to the center thereof, which presents also a seal that extends in the opposite direction. On the opposite side of the oil outlet, preferably there are several tongues that serve to locate the seal in its environment. One of the components of the seal includes a cover element which preferably has a cover associated therewith with an off-center area which serves to define, in combination with the main body unit, an oil passage. This cover is retained in the main body unit by a series of tabs and preferably also by adhesive that surrounds the formation but leaves the oil inlet free. The differential housing includes a sump, and therefore the oil seal has an opening at the bottom, an area of thin dimension, and preferably enlarges, leading to the oil outlet opening in the seal, and ending in the opening. The differential housing contains a pinion or drive gear, which serves to rotate a ring gear and its associated components, at a reduced speed relative to the pinion gear. Referring again to the side with the opening, this side is oriented towards the opening in the ring gear for the entry of an oil pump. The pump consists of two gears or rotors that rotate at different speeds relative to one another within a housing. Preferably, the parts are of a "Gerotor" design that admits the oil through the opening into a cover plate that is partially inside the ring gear and forces the oil out in the opposite axial direction against a linked piston to operate a multi-plate clutch.

The gear pump includes an outer housing, an internal rotor and an external rotor. The 'inner rotor includes teeth in its internal diameter to attach an axis and has formations directed outwards' in the same, and the external gear has internal formations in it. These two, together, form an oil pump having an inlet on an axial side and an outlet I on the opposite axial side, with the inlet and the outlet being separated by approximately half | of a diameter. The oil is then pumped into a cavity in a housing containing a bonded piston. Upon detecting the oil pressure, the piston moves to compress the discs of a multi-plate clutch and eventually causes the drive shafts to rotate together. A drive shaft extends through an opening in the ring gear, and this drive shaft is slotted to fit within the Gerotor's internal gear, the driven clutch plates, and one of the side gears of the satellite kit. The second shaft is internally grooved towards the other side gear. When the oil acts on the linked piston, it tends to block the internal grooves of the first arrow to the second arrow, blocking out the carrier, thus causing both arrows to rotate as a unit, without requiring a differential action.

When the linked piston sees less oil pressure, it releases its hold, allowing the clutch plates to be released to a greater or lesser degree, and the differential is then released to provide a greater or lesser differential action. Correspondingly, an object of the present invention is to provide an overpressure seal having certain advantages and characteristics. Another object of the invention is to provide an overpressure seal that is sealed in two diameters, which includes an oil passage therethrough, which extends from both diameters to an intermediate point of the two diameters. Still another object of the invention is to provide an oil seal that is manufactured from inexpensive pieces, preferably die-cut. Still another object of the invention is to provide a seal having three components, one of which comprises a cover for a part of the other. A further object of the invention is to provide an overpressure seal having a flat plate with an OD seal, an aperture in the flat plate, a stamp with an I: D seal, and a cover, preferably of a design contoured, which fits over the flat plate to provide a line or oil supply area to a certain part of an associated pump mechanism. A still further object is to provide an oil seal that includes tabs to prevent rotation and thereby ensuring that the seal will remain in place relative to a rotary ring gear assembly. Another object of the invention is to provide an oil seal of a design which can generally be followed in practice in a number of different sizes and which will serve to fulfill the requirements for an effective oil seal for a closing differential. Still another object of the invention is to provide an oil seal that includes a flange provided with a spring, on the internal sealing surface, and a non-spring loaded edge on the external sealing surface, with the two edges oriented in opposite axial directions. . Another object of the invention is to provide an oil seal assembly having opposingly directed seals, an oil supply pipe, and an oil outlet, with the supply pipe remaining on the side opposite the seal of the external diameter. A further object of the invention is to provide a seal assembly with an oil collector on one side of the outer diameter seal, and an oil discharge opening on the other side. A still further object of the invention is to provide a seal assembly that can maintain a volume of oil in the space between the two seals, to supply the needs of an oil pump from time to time. The invention achieves its objects, and other inherent objects as well as the advantages by providing an overpressure seal for a differential ring gear assembly, the seal including a portion that is sealed in an internal diameter of an associated part during use with the gear of ring, and an oil pump housing, and a portion that is sealed in the enlarged diameter of this part to create a seal region therebetween, an oil outlet in the area between the seal, and an oil inlet which is outside the sealed area, whereby the oil can be collected and pumped from a sump to a specially constructed differential, where it will serve, under the appropriate conditions, to lock together the driving shafts and allow it to be applied to both shafts a considerable torque. The manner in which the aforementioned objects and other objects are achieved in practice will be more clearly evident when reference is made to the following detailed description of the present invention and the accompanying drawings, wherein like numbers indicate the corresponding parts.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a horizontal sectional view showing the seal of the invention associated with a differential containing a ring gear assembly, and numerous other components to be described in detail, including a pair of opposing driving shafts; Figure 2 is a perspective view of one end of the ring gear, with the axes not being shown for reasons of clarity, showing the seal in its position of use adjacent to the housing of the oil pump and illustrating the tongues of placement before they are clamped over the bearing caps with which they are associated during use; Figure 3 is a perspective view of the other side of the ring gear overpressure seal assembly of the invention, showing the outer diameter seal and the oil outlet passage between the external and internal seals.

Figure 4 is an almost vertical sectional view taken along lines 4-4 of Figure 3, and showing the cover assembly cooperating with the main body plate to form an oil passage; Figure 5 is a sectional view, taken along lines 5--5 of Figure 3 and showing the internal seal unit pressed towards the body of the main seal; Figure 6 is an assembled view of the oil pump housing, and the Gerotor type oil pump, showing both rotating components thereof and a portion of the high pressure channel facing the outlet side; Figure 7 is a view similar to Figure 5, but showing the Gerotor-style pump removed and showing the oil pump housing with both the inlet holes and the outlet formation for the oil pump associated with the pump. invention; Figure 8 is a side elevational view of another embodiment of the invention; Figure 9 is a view from the other side of the seal of Figure 8; and, Figure 10 is a sectional view of the seal of the invention showing the taper between the seal body and the cover and showing the oil inlet and outlet in the plate and cover.

DESCRIPTION OF THE PREFERRED MODALITIES OF THE INVENTION The seal of the present invention has a primary use, and that is with a blocking differential, particularly of the type described. However, with or without modifications, it may provide other uses where its particularities are advantageous, namely, the filling and maintenance of an oil reservoir between the inner and outer diameter seals, and between a sealed part and two elastomeric seals of the device of the invention. Referring now to the drawings in greater detail, Figure 1 shows the unit of the invention to be encompassed in an overpressure seal form generally designated 18, shown as being associated during use with a differential mechanism designated generally 20, and contained within a housing 22 for the differential assembly 20. Here, a pinion shaft 24 drives a conventional pinion gear 26 which in turn couples and drives a ring gear 28. Fasteners, such as cap screws 27 or the like, connect the ring gear 28 with a pump housing 30. A Gerotor type oil pump 31 (Figure 6) is in a type of internal-external rotor of a type known to those skilled in the art, and it includes an inner rotor 32 and an outer rotor 34. These rotors, as is known to those skilled in the art, function by providing a space that gradually increases 35 The teeth where the oil is taken axially into the space between the gears, transferred radially, and then ejected axially from the gap 37 between the teeth as the rotors converge. The pump operates in conjunction with the multiple inlet passages 36 (Figure 7) in the housing, and in connection with a recess 38 that forms a part of an associated outlet to which reference will be made elsewhere herein. Referring again to the differential ring gear 28 in Figure 1, in addition to the pump housing 30, the ring gear also has a satellite carrier 42 fixed thereto. This satellite carrier includes a satellite gear arrow 44 carrying a pair of satellite gears 46, 48 which in turn coincide with the gears side 50, 52. Each of the side gears is grooved on an axis 54, 56, with a pair of shafts 54, 56 that operate in accordance with generally known principles, that is, they will work together, or, in the case of an unbalanced load, the differential will allow one to turn and the other to remain stationary, to any necessary degree. However, the present invention differs considerably from the prior art by being associated with a novel modified differential set. In this new version, in addition to the novel overpressure seal 18, and of the known satellite carrier 42, the satellite gear arrow 44, the satellite gears 46, 48 and the side gears 50, 52, the satellite carrier 42 includes a large recess 58 which accommodates, among other things, a plurality of clutch driving plates 60 wedged to the protractor 42, and a plurality of clutch driven plates 62 slotted in an internally toothed gear 64 which is then slotted on an axis 56. In addition, the satellite carrier 42 contains, near its end axially outwardly, (the left end as shown in Figure 1) and within the recess 58, a bonded piston assembly designated generally 66, comprising a generally designated housing 67 that includes a short wall outer cylindrical 68, an internal cylindrical short wall 70, a perforated rear wall 72, and a bonded piston assembly designated generally 74. The piston assembly it includes an oil seal on its external diameter 76, an oil seal on its internal diameter 78, a radially internal face 80 and a radially external face 82 that is slightly offset to the clutch plates 60, 62. Oil 84 is drilled in the piston 74 and the opening 84 includes therein a radial passage 86, to allow an exact amount of oil to be discharged therefrom. The housing 67 of the bonded piston also contains a plurality of positioning projections 88. In addition, the rear wall 72 of the housing 67 contains a plurality of openings 90 for the oil which, under appropriate conditions, passes from the oil pump 31 and endows of pressure to the linked piston 74, pushing it to the right as shown in Figure 1. Referring now to the first embodiment of the oil seal of the overpressure type 18 of the invention, this unit is shown in different positions in Figures 2 to 5, as well as in the sectional view of Figure 1. The overpressure seal designated generally 18 is shown as consisting of a generally designated main body plate 94, a plate cover generally designated 96, and an insert of generally designated seal 98. The main body plate 94 includes the tabs 100, 102 to prevent rotation of the overpressure seal 18 around its pr opium axis. During installation, the tabs 100, 102 are fitted over a bearing cap or other fixed part to prevent rotation of the seal 18. The main body plate 94 also includes an opening 104 for the oil outlet, and a seal of large diameter oil extending axially inwardly adjacent to its outer diameter. A plurality of tabs 108 are also formed in the main body plate 94 for retaining the cover plate unit 96 in place above the plate 94. The generally designated cover unit 96 includes a raised central portion 110, and a margin 112 that remains above the main body plate 94 in the rest of the area. The cover 96 is preferably also adhesively secured to the main body plate 94, and then attached in place with the tongues 108. An oil pickup opening 114, as shown in Figure 4, is provided in the lower part of the plate 94 and the cover 96 for the oil inlet. The raised portion of the cover 110 has a gradually increasing depth (from the bottom to the top as shown in Figure 4) as it extends from its entrance to the outlet in the middle part of the seal assembly 118 , and also a dimension of the front part to the rear part which decreases to a certain extent as the middle part of the seal assembly 18 approaches. The cross-sectional area of the oil passage therefore, generally speaking , it remains approximately constant from the lower part to the upper part of the oil passage. Referring now to the seal insertion piece 98, FIG. 5 shows this unit being pressed in fluid-tight relation in an opening 120 formed in the main body plate 94. The assembly includes a relatively rigid die or other outer box 122. , an elastomeric oil seal body 124, and "air" side and "oil" side surfaces 126, 128 that meet along a generally circumferential site defining a seal band 130. The surfaces of the The "air" side and the "oil" side are conventional in the seal branch and refer to the outer space oriented surfaces as well as the enclosed space respectively. In the present case, however, it will be understood that the oil exists on both sides of the seal. Under some conditions, an oil bath is retained between the seal of room 30, and in this sense, there is more oil in this area. The elastomeric seal body 124 also includes an optional spring groove 132 in which a spring 134 is placed for additional radial load. Additional tongues or lugs 136 are also provided to allow oil to enter the area and lubricate the bearing and seal. The tabs also provide a "stay away" function; that is, they serve as separators for the installation. Referring now to the operation of the overpressure seal 18 of the invention, it will be assumed that the ring gear is in place with the oil pump housing above it. The oil pump housing 30 houses the pump 31, and in addition, includes the rear surface 140, which has a cylindrical formation of external diameter extending rearward 142 and a cylindrical formation of internal diameter 144 as well as a plate extension 146 which is separated at a certain distance by an opening 148 from the shaft 54. With the exception of the openings that form part of the inlet passages 36, the rear plate 140 of the housing 30 is not perforated. The overpressure seal 18 is generally fitted above the plate 30, with the seal 106 tightly engaging the cylindrical formation 142 in fluid-tight relation. In the inner diameter, the elastomeric seal body 124 fits snugly above the cylindrical surface 144 so that the seal band 130 engages the cylindrical surface 144. As a result, there is an oil tight space 150 between the seal 18 and the rear surface 140 of the pump housing. When the shaft rotates relative to the ring gear, as is occasionally allowed by the satellite gears, the inner rotor 32 rotates with respect to the outer rotor 34. This creates a vacuum in the space 37 and draws the oil up the vertical passage 152 from the lower exit 114, outwards! of the opening 104 in the main body plate, thereby filling the space 150. From here, the oil proceeds through the opening 37, and finally out of the space 38, through the openings 40 and the space 66 behind the linked piston 74. Except for the small amount that escapes controllably out of the opening 84 and through the passage 86, the system is fluid-tight. The oil pressure in this way forces the plates 60, 62 together, ultimately rotating the carrier as a whole, and causing the gears 52, 50 to rotate together as a unit. As the elements continue to rotate, the oil pump operates and the clutch plates remain forced together. When the force tending towards the drive of the gears at different speeds is decreased, then the speed of the pump decreases and the hydraulic force is reduced. The axes are gradually released to rotate at approximately the same speed. As long as the axes are rotating at almost (or exactly) the same speed, the pump will not work. However, in this case, it will not be necessary in order to ensure that both axes rotate at the same speed. It is only when one axis begins to rotate in relation to the other that this action is carried out. If you turn the shaft to the right 54, relative to the left-hand axis 56, the result is still the same as the pump 31 will be driven by the shaft in any case. In this case, the assembly will still be blocked, and a torque will then be transmitted equally to both axes. Referring now to Figures 8, to 10, a slightly different embodiment of the invention is shown. Here, a main body plate 194 is shown, having an insertion piece 198 pressed into the opening 220. The oil hole or outlet 204 is the same, as are the external diameter seal 206 and the body of the valve body. inner diameter seal 124. The tabs 200, 202 are in a slightly different location as are the tabs 236. However, they serve the same function as their duplicates in the aforementioned example. Referring to the cover 196, this includes the raised portion 210, and the tabs 208 that are secured in place are the same. Oppressed margin 212 is also the same or similar. However, the cross section is somewhat different, with the cover assembly 196 having a contoured raised portion 210. The plate 194 of the unit includes a decentered portion 195 near the bottom, and the cover plate has a depth that increases gradually as it approaches the top, thereby maintaining the cross section of space 252 generally constant. Other variations may be made to the shape of the seal shown in the drawings. In the two seal forms shown in the drawings, the admission for the oil is shown as the space between the plate and the cover. Preferably, this places the oil intake just outside the diameter of the outer seal. If for some reason an oil pick-up piece can not be found in another location, that is, with a considerable axial offset, the oil passage could be in the form of a tube or the like extending in fluid-tight relation from the exit of the oil to an appropriate place in which the capture would take place. Plate 94 is shown as being flat or nearly flat, but there is no reason other than an economy reason why it can not contain one or more off-center or indentations. The seal is shown without spring in the external diameter; however, this seal element could have a spring so that the internal diameter could be increased. Other variations will occur to those skilled in the art. Therefore, it will be seen that the present invention provides a combination of seal and oil steering device having a number of advantages and features including those expressly stated herein, and others that are inherent in the invention. Two illustrative embodiments of the product of the invention have been shown and described and it is anticipated that some variations will occur to the shape of the apparatus described by those skilled in the art and that these modifications and changes can be made without deviating from the spirit of the invention. , or the scope of the appended claims.

Claims (19)

CLAIMS:

1. An overpressure seal assembly, comprising, in combination, a generally flat plate assembly with radially internal and external margins and including a first oil seal body adjacent to the outer margin thereof, and a second adjacent oil seal assembly. to the internal margin thereof, an oil outlet opening in the plate remaining between the inner and outer margins, the plate includes a portion extending radially outwardly beyond the outer margin, and a cover for the plate, the cover it generally extends from a radially outward location from the outer diameter seal body to a point generally adjacent to the oil outlet opening and cooperates with the plate to define an oil passage and an oil inlet opening, the cover is sealed in essentially fluid-tight relation to the plate except for the inlet and outlet openings, the thus, an assembly for collecting the oil from a sump remaining outside the outer diameter margin and supplying the oil to a mechanism having an oil inlet radially between the seal bodies is provided.

An overpressure seal assembly according to claim 1, wherein the generally flat plate has at least one tab therein to prevent rotation of the overpressure chamber assembly relative to a mechanism that is being sealed.

3. An overpressure seal assembly according to claim 1, wherein the second oil seal assembly adjacent to the inner margin comprises an internal marginal opening, and a seal box extending through the opening in airtight relationship. to the fluid, the second oil seal assembly includes an elastomeric body attached to the housing.

4. An overpressure seal assembly according to claim 3, wherein the box of the second oil seal includes at least one tongue thereon for coupling an associated part.

5. An overpressure seal assembly according to claim 1, wherein the first oil seal body extends in an axial direction and the second oil seal assembly includes a body extending in an opposite axial direction.

6. An overpressure seal assembly according to claim 1, wherein the first oil seal body is a spring-free seal body.

7. An overpressure seal assembly according to claim 1, the second oil seal assembly comprising a case and an oil seal body linked to the inner diameter portion of the case, the oil seal body having air and oil side surfaces that meet along a generally circular site to provide a proposed contact seal band with an associated part, the case being press-fitted on the internal margin of the plate.

8. An overpressure seal assembly according to claim 7, wherein the oil seal body of the second oil seal assembly includes a spring groove with a spring positioned thereon to provide additional radial load.

9. An overpressure seal assembly according to claim 1, wherein the cover is retained adjacent to the generally flat plate by a plurality of tabs bent over each other.

10. An overpressure seal assembly according to claim 1, wherein the cover is retained in its adjacent location in the flat plate by a plurality of tabs pressed above and further by a layer of adhesive extending around the entire surface. the external margin of the cover, except for the oil entry.

11. An overpressure seal assembly, comprising, in combination, a plate having a main body portion and a first oil seal body extending around the entire periphery thereof and which is designed to be sealed at the first enlarged diameter of an associated part, an opening at the center of the plate, an oil outlet opening between the first seal around this periphery and the opening in the center of the plate, a second oil seal assembly includes a box portion and an elastomeric seal body secured in the portion of box, the second oil seal assembly is pressed towards the opening, the second seal body has surfaces on the air side and on the oil side that meet along an essentially circular site to form a seal band intended to come into contact with a sealed part in the second smaller diameter than in this sealed part, and an oil passage extending from the oil outlet opening to a region to the former At the outer periphery of the seal, the region sealed between the first and second seals is not perforated from one side when installed, except as it relates to the oil outlet opening.

12. An overpressure seal assembly according to claim 11, wherein the first oil seal body and the elastomeric seal body of the second seal body assembly extend in axially opposite directions.

13. An overpressure seal assembly according to claim 11, wherein the oil passage comprises a part of the plate and a cover for the plate.

14. An overpressure seal assembly according to claim 13, wherein the cover is secured to the plate by a plurality of tabs.

15. An overpressure seal assembly according to claim 14, wherein the assembly also includes an adhesive placed between the cover and the plate.

16. An overpressure seal assembly according to claim 11, wherein the plate includes at least one tongue extending in contact with a portion of the associated machine to prevent rotation of the seal assembly during use.

17. An overpressure seal assembly according to claim 11, wherein the portion of the box of the second oil seal includes tabs adapted to be in a position adjacent another set to separate the seal relative to the other set.

18. In combination, an oil seal assembly and a rotating part with a ring gear in a differential mechanism, the rotating part has a circular site of a larger first diameter and a second site of a smaller second diameter both of the sites generally having near-cylindrical surfaces extending circumferentially, the oil seal assembly having a first seal of a larger diameter and a second seal of a smaller diameter, the seals being adapted to coincide in tight sealing relationship respectively with the cylindrical surfaces, the oil seal further includes at least one plate member in relation to which the first and second seals are placed, an opening in the plate member serving as an oil outlet and an inlet oil placed far from the oil outlet with a passage that extends from the entrance to the exit, and with the member not standing or perforated between the first and second seals except in regard to the oil outlet, and the seals and plate member being adapted to maintain an oil bath in the space between the seals and the rotating part below at least some conditions.

19. An overpressure seal comprising, in combination, a plate having a first circular oil seal adjacent to an outer diameter margin thereof and an internal margin containing a second oil seal, thereby defining a space between the plate, the first and second seals, and an associated machine part, an oil outlet opening communicating with the space, and a means defining an oil passage extending from the oil outlet opening to a site separated from the space to provide a piece of catchment of the oil during the demand for it and to direct the oil from a place within the space to an area within it.