Abstract:
A specialized mounting arrangement for an accessory such as an engine driven air conditioner compressor to an engine is utilized featuring a pair of press fitted bushings in a pair of arms of the mount and a single bolt extending therethrough. The arms of the mount assembly are constructed so that they straddle portions of an anchor member attached to the engine. A connector bolt is inserted through one bushing in one arm of the mount and then thorough a passage in the anchor member, and next into engagement with internal threads carried by the other bushing which his carried by the other arm of the mount. Rotation of the bolt moves the bushings toward one another and against the ends of the anchor member to clamp the anchor and thus the accessory therebetween. This clamping construction permits the accessory and mount to be adjusted axially relative to the bold so the accessory can be aligned relative to the engine drive arrangement before the accessory is finally affixed to the engine in a non-adjusting fashion.

Description:
FIELD OF THE INVENTION 
     This invention relates to the use of mounts for engine accessories and more particularly to a new and improved method of mounting an accessory which facilitates axial aligning the accessory. 
     BACKGROUND OF RELATED ART 
     Prior to the present invention various bracket constructions have been devised and utilized to mount automotive accessories to the engine so that they can be driven thereby and are accessible for service. Examples of such prior art are found in the following U.S. Pat. No. 3,730,147 to Buckwald for Engine Accessory Arrangement; U.S. Pat. No. 5,065,713 to W. Seats for Mounting Brackets For Mounting Engine Accessories; and U.S. Pat. No. 4,633,828 to L. Steele for Adjustable Polar Point Mount. While these prior art arrangements provide various constructions for accessory mounting and generally meet their objectives, they do not meet new and higher standards for attaching and supporting an accessory at a first point directly to the engine and then providing axial shifting of the accessory and mount for aligning the accessory for final attachment to the engine by at least one fastener. Moreover and in contrast to the present invention, the prior art mounting constructions and methods are not readily adaptable for accommodating relatively large tolerances common in mass produced components. Also, they do not conveniently and rigidly anchor the accessory at multiple attachment points to the engine so that the accessory is permitted to be axially shifted for positioning in a predetermined desired location for subsequently receiving a fastening member which finishes the attachment of the accessory to the engine and which is capable of handling relatively great torque inputs by a drive belt driven by the engine crankshaft. Furthermore, the prior constructions do not provide for material savings of engine compartment space and for self-locking and self-aligning with respect to the supporting structure. 
     BRIEF SUMMARY OF THE INVENTION 
     In vehicle applications, it is often desirable to mount accessory components such as the air conditioner compressor directly to the engine. Because engines have been downsized and engine components have become more cramped, the need has arisen to mount engine driven components by new arrangements and methods. Preferably, the arrangement should space the accessory close to the engine and in an accessible location to enhance service as well as to effectively utilize limited engine compartment space. The new and improved mounting arrangement of this invention meets such needs and requirements in one straightforward unit. More particularly, the mounting arrangement of this invention utilizes a pivotal lower mount assembly with two spaced arm portions having apertures therethrough in which a pair of press fitting bushings extend. A single fastener such as a threaded bolt extends through the two bushings and through a corresponding passage in the accessory which is positioned between the two arm portions. Preferably, one bushing is internally threaded to mesh with threads on the bolt and provision is made to eliminate rotation of the bushing and thus a need for an assembly tool such as a wrench to prevent rotation of the bushing during assembly. Subsequently, the accessory is pivoted about the single fastener of the lower mount so that another fastener can be utilized to firmly attach the accessory to the engine. This invention can be used to mount a variety of components particularly where additional remote mountings are used in conjunction with the mounting provided by this invention. 
     It is a feature, object and advantage of this invention to provide a new and improved mounting arrangement to facilitate connection of an accessory such as an air conditioner compressor to the vehicle engine. The mounting arrangement provides a self-locking and self aligning function prior to finally securing the accessory to the engine. The mount arrangement employs non-rotatable, axially sliding bushings that adjust axially to accommodate tolerance stack-up variations between the arms of the mount and the corresponding attachment structure of the accessory. Turning of the mounts single connecting bolt which extends through the mount arms and the attachment structure creates forces which axially move the bushings toward one another and against the engine&#39;s mount structure. This axial movement clamps and secures the accessory to the bushings and to the engine attachment structure. Due to the action of the sliding bushings, no undue axial clamp force is imparted to the arms of the mounting assembly or frame which could result in damaging the arms. Further, after attachment by the above described mount, the accessory can be pivoted and moved in an axial direction to position the accessory for final attachment to the engine by means of a fastener, such as a cap screw. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     These and other features objects and advantages of the present invention will become more apparent from the following detailed description and drawings in which: 
     FIG. 1 is a pictorial view of a bottom portion of an internal combustion engine with an engine driven air compressor mounted thereto; and 
     FIG. 2 is an enlarged cross sectioned view of a part of an aligning and locking mount assembly attaching the air conditioner compressor to the engine taken generally along sight lines  2 — 2  of FIG. 1; and 
     FIG. 2 a  is a sectioned view of part of the mounting assembly shown in FIG. 2 in which the connection bolt is in its pre-assembled position of the mount assembly: and 
     FIG. 3 is an enlarged pictorial view of a first bushing used in the aligning and locking mount assembly of FIGS. 2 and 2 a ; and 
     FIG. 4 is an enlarged pictorial view of a second bushing used in the aligning and locking mount assembly of FIGS. 2 and 2 a ; and 
     FIG. 5 is a pictorial view similar to FIG. 1 but showing the attachment of upper arm portions of the air conditioning compressor to the engine; and 
     FIG. 6 is an end view of the engine of FIG. 1 illustrating another view of the attachment of the air conditioning compressor to the engine by the mounting assembly and by the upper attachment arms; and 
     FIG. 7 is a pictorial view of another embodiment of the invention illustrated by an accessory with integral mounting attachment arms that incorporate the features of the separate aligning and locking mount component shown in FIGS.  1 - 6 . 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Turning now in detail to the drawings there is shown in FIG. 1 an accessory in the form of air conditioning compressor  10  having an input drive pulley  12  on the outboard end thereof conventionally driven by the engine crankshaft mounted pulley  13  through a serpentine drive belt  14 . The compressor  10  is shown in a partially assembled condition operatively connected to the engine by a lower mount assembly  16 . Specifically, the compressor  10  is mounted to the engine&#39;s oil pan  20  by mount assembly  16 . The oil pan  20  in turn is attached to the engine block  22  of the vehicle engine  24  by screws  26 . A gasket  28  is interposed between the oil pan  20  and the engine block  22  to effect fluid sealing between these two components. 
     In FIGS. 5 and 6, the compressor  10  has been pivoted (counterclockwise in FIG. 6) to the final assembly position for connection to the engine block  22 . This connection is in addition to the connection provided by the lower mount assembly  16  to the oil pan  20 . Specifically, a pair of laterally spaced upper arms  30  and  32  of the compressor are directly attached to engine block  22  by fastener screws  34 . These upper arms  30 ,  32  extend outwardly from opposite end portions of the compressor housing and are attached at their distal ends by the screws  34  which are adapted to thread into the internally threaded and laterally spaced bores  36  and  38  formed in the engine block  22  at remote points from the lower mount assembly  16 . 
     Because the upper and lower connections of the compressor  10  are to different components of the engine (oil pan  20  and engine block  22 ) and since these different components are likely to be furnished by different suppliers, perhaps from more than one country, the design of the lower mount assembly is required to automatically compensate for limit stack (quantity production variation in parts tolerance) between the engine components and also between oil pan positioning and the anchor points by which the lower mount is attached to the accessory. 
     In a preferred embodiment, the lower mount assembly  16  has a generally rectilinear attachment or base frame  40  which has a pair of laterally extending attachment wings  42  located on opposite ends of the base  40 . As seen in FIG. 6, wings  42  have aligned fastener openings  43  formed therein which align with threaded openings  44  formed in corresponding radically extending lug portions  46  of the housing of the compressor  10 . Threaded fasteners  48  extend through the openings  43  in the wing portions and are threaded into the corresponding openings  44  in the lug portions  46 . This securely couples the mount assembly  16  to compressor  10 . 
     A pair of laterally spaced apart attachment arms  50 ,  52  of base frame  40  project away from and upwardly in FIG.  1 . As seen in FIGS. 2,  2 A, the arms  50 ,  52  of base frame  40  have cylindrical and axially aligned through-passages  54 ,  56 . These passages respectively receive split bushings  58  and  60  which are press fitted in the passages  54 ,  56 . The bushings are sized to frictionally fit in their passages so that they will not turn after being press fitted therein. Bushings  58 ,  60  may be conveniently made from powdered metal. 
     Details of preferred bushings  58 ,  60  are best shown in FIGS. 3 and 4. Bushing  58  has a generally cylindrically and tubular body  62  which extends axially from an enlarged and circular head portion  64 . The body  62  and head portion  64  are split lengthwise by a longitudinal slit  66  allowing it to readily accommodate a range of diameters of passages  54 . When the bushing  58  is inserted into the passage  54 , the tubular body  62  is squeezed to effect a degree of closure of the slit  66 . The recovery force exerted by body  62  in attempting to recover its relaxed configuration will frictionally hold the bushing in the passage  54  and inhibit rotate. The inner diameter cylindrical surface  67  of bushing  58  is preferably cylindrical and smooth and has a dimension sufficient to accommodate passage of the cylindrical shank  70  of a connector bolt  72  therethrough as seen in FIGS. 2 and 2A. 
     The other bushing  60  is generally like bushing  58  and has a cylindrical tubular body  74  and a contact head portion  76 . As with bushing  58 , the bushing  60  has a longitudinal slit  78  therein to create a tight press fit of the bushing in various diametered openings such as passage  56 . Thus bushing  60  is held in passage by its natural recovery force exerted outwardly against the walls of the passage. In addition, the body  74  of bushing  60  is internally threaded with a helical thread  80  for meshing with a corresponding thread on the end portion  82  of the bolt  72 . 
     The head portion  76  of bushing  60  also has a radially outwardly extending protuberance or tab  84 . Tab  85  is designed to physically contact a raised stop  86  extending upward from the upper surface of the base  40  of the lower mount  16 . This contact prevents rotation of the internally threaded bushing  60  as the bolt  72  is rotated from the pre-assembly position of FIG. 2A to the assembled position of FIG.  2 . As attachment bolt  72  threads into the threaded opening  80  of bushing  60 , the bushings  58 ,  60  are axially moved toward one another into a position where the head portions  64 ,  76  engage the compressor housing. 
     In this embodiment, the oil pan  20  is an aluminum casting formed with an integral and projecting accessory anchor portion  90 . As best seen in FIG. 2, the anchor portion  90  includes a pair of laterally spaced and outwardly projecting attachment arms  92 ,  94 . The arms  92 ,  94  have aligned openings  96 ,  98  of sufficient diameter to allow the shank  70  of bolt  72  to pass readily therethrough. The outboard side surfaces  100 ,  102  of arms  92 ,  94  are flattened for optimizing physical contact with the correspondingly flattened outer surfaces  104 ,  106  on the bushings  58 ,  60  when in a fully clamped and locked position assembled condition. 
     Preferably before assembly of the compressor  10  to the engine at the factory, the accessory mount assembly  16  is pre-installed on the compressor  10  so that its laterally spaced arms  50 ,  52  can then be conveniently positioned to straddle the arm portions  92 ,  94  of the anchor portion  90  of the oil pan  20 . In this pre-assembled condition, bushings  58  and  60  are inserted into the passages  54 , 56  and separated by a sufficient distance to accommodate a wide tolerance in the dimension of the anchor portion  90  of the oil pan. After the openings in the arms  92 ,  94  of the anchor portion  90  and the openings in the arms  50 ,  52  of the mount  16  are aligned, the bolt  72  is inserted through the first bushing  58 , the openings  96  and  98  in the arms  92  and  94  of the anchor  90 , and then into threaded engagement with the bushing  60 . This stage of assembly is illustrated in FIGS. 1 and 2A. 
     Next, the enlarged polygonal head  110  of the bolt is turned by suitable tooling, such as a torque wrench to advance the bolt  72  into the threaded bushing  60 . When the flattened side  112  of the bolt head engages the end  114  of bushing  58 , the resultant inwardly directed force F-R of the bolt on the bushing  58  moves it to the right in FIG.  2 A. Meanwhile, the threaded connection of bolt  72  and bushing  60  creates an inwardly directed pulling force F-L on bushing  60  causing its movement to the left in FIG.  2 A. These forces F-R and F-L cause movement of the bushings  58 ,  60  toward one another. While the bushings are moved toward one another, they are inhibited from rotation in their associated passages  54 ,  56  by the press-fit therein. Also, the entry of the screw section of the bolt  72  into the corresponding threaded portion of bushing  60  creates a radial expansion effect which creates gripping force between bushing  60  and arm  52  to further secure this bushing against rotation. 
     The aforedescribed inward sliding movements of bushings  58 ,  60  continues until the end portions  64 ,  76  of bushings  58 ,  60  engage side surfaces  100  and  102  of arm portions  92  and  94 . The resultant forcing of bushing  58 ,  60  against the surfaces  100 ,  102  of the anchor portion  90  further keep the bushings from rotation. 
     The above described sliding movement of bushings  58 ,  60  results in positioning of the compressor structure and self-alignment relative to the anchor portion  90  located between the spaced arm portions  50 ,  52  of the mount assembly  16 . Once the compressor  10  fixed by engagement of the ends of bushing  58 ,  60  with the anchor portion, they are positioned in a desired axial operating position relative to the anchor. Thus, the outboard pulley portion  12  is aligned with the associated pulley  13  on the engine&#39;s crankshaft. This makes for a smooth transfer of driving power through the serpentine belt  14 . 
     Moreover, with the above described sliding, clamping, aligning, and locking arrangement, the arm portions  50 ,  52  of mount  16  are not subjected to bending forces which might fractured them of otherwise damage them. This is because the clamping forces are routed through the bushings  58 ,  60  and on to the opposing side surfaces  100 ,  102  of the rigid anchor arms  92 ,  94 . 
     The clamping and locking action shown in FIG. 2 is accomplished subsequent to the initial connection of the mount  16  to the anchor portion  90  as seen in FIG.  2 A. Next, as illustrated by means of arrow “A” in FIG. 6, the accessory or compressor  10  can then be pivoted counterclockwise about the axis of bolt  72  to the final assembled position shown in FIGS. 5 and 6. Likewise, when the compressor is serviced by being replaced for example, the fasteners  34  can be removed and the compressor  10  can then be pivoted clockwise in FIG. 6 to a more accessible position. In either situation, the axial position of the compressor  10  can be adjusted by axial shifting of the bushings  58 ,  60  in passages  54 ,  56  before the compressor is firmly attached to the engine block  22  by fasteners  34  extending through apertures in upper arms  30 ,  32  and into treaded openings  36 ,  38 . With the compressor  10  secured at its upper arms  30 ,  32 , the bolt  72  is then be tightened to a desired torque which completes the mounting operation of the compressor  10  to the engine. As bolt  72  is rotated during this final step, threaded bushing  60  is inhibited from rotation in passage  56  by interaction between tab  84  and raised portion  86 . 
     FIG. 7 illustrates a modification of the invention in which the locking mount assembly includes laterally spaced arm portions  200 ,  202  which are integrally formed from the accessory or compressor housing  204 . The associated bushings and other componentry of the mount arrangement remain substantially the same as in the previously described embodiment. If desired, these bushings could be keyed or splinted into the arms  200 ,  202  to allow their clamping action while preventing their rotation. 
     Modification and variation to the structure and operation of the present invention are contemplated in light of the disclosure of preferred embodiments of this invention. It is therefore to be understood, that the operation of the invention may be practiced in other manners than as specifically described.