fig1 illustrates an automatic cooking machine 2 incorporating a flipping assembly 4 made according to the invention . the details of the automatic cooking machine except for flipping assembly 4 do not generally form a part of this invention . however , some of the drive components , shown in more detail in fig3 and 3a , will be described for a complete understanding of the invention . the components of cooking machine 2 , with the exception of flipping assembly 4 , can be of the type disclosed in u . s . pat . no . 4 , 649 , 810 to wong . cooking machine 2 includes a motor / controller housing 6 containing a drive motor and a microprocessor - based controller , not shown . machine 2 also includes a cooking vessel 8 supported by a heating base 10 and covered by a lid 12 . a drive assembly 14 extends from motor / controller housing 6 and is used to suspend and drive flipping assembly 4 within cooking vessel 8 through lid 12 . referring now primarily to fig2 and 3 , flipping assembly 4 includes broadly a u - shaped frame 16 , a lifting assembly 18 mounted to frame 16 , a food carrier 20 mounted to lifting assembly 18 for vertical movement and a food carrier rotator assembly 21 which rotates food carrier 20 about a horizontal pivot axis 22 . frame 16 includes a pair of u - shaped members 24 , 25 secured to one another by a coupler plate 26 . coupler plate 26 has a cylindrical coupler 28 extending upwardly therefrom for the purposes to be discussed below . u - shaped member 24 includes a pair of arms 30 coupled by a bight 32 , while u - shaped member 25 includes arms 30 , 31 coupled by a bight 32 ; each arm 30 , 31 has a vertically extending guide slot 34 formed therein . guide slots 34 are used to guide and orient tabs 36 extending from support plates 38 , support plates 38 being parts of lifting assembly 18 . each support plate 38 includes an upper extension 40 having a slot 42 formed therein for receipt of the distal end 44 of a pivotal lifting arm 46 . lifting arms 46 are also part of lifting assembly 18 and are pivotally mounted to frame 16 at pivots 48 . the way by which lifting arms 46 are raised and lowered will be discussed below . food carrier 20 may take a variety of configurations depending on the food being held . in the disclosed embodiment , food carrier 20 includes a pair of side members 50 each having a support shaft 52 rigidly attached thereto and extending horizontally therefrom along pivot axis 22 so to be journaled within support plates 38 . a pair of food piercing rods 54 are removably mounted to the ends of side members 50 so that a piece of food , such as a piece of meat , can be positioned between side members 50 and held in place by being impaled by rods 54 . rods 54 can be held in place through a friction fit , threads or other attachment elements . food carrier 20 is rotated by food carrier rotator assembly 21 . food carrier rotator assembly 21 includes a star wheel 58 rigidly secured to support shaft 52 so that star wheel 58 rotates with food carrier 20 . star wheel 58 has two pairs of cam pins 60 / 61 , 62 / 63 adapted to engage cam surfaces 64 , 66 formed on arm 31 of u - shaped member 25 as lifting arms 46 raise support plate 38 thus causing star wheel 58 to rotate . it should be noted that cam pins 60 , 61 are positioned along axis 22 to engage cam surface 64 while cam pins 62 , 63 are positioned to engage cam surface 66 . while two star wheels 58 and associated cam surfaces 64 , 66 could be used , one star wheel should be sufficient to rotate food carrier 20 . the rotational sequence can be seen best with reference to fig4 a - 4d . fig4 a illustrates food carrier 20 at a first elevation and at a first rotary orientation . the leftmost end of side member 50 is marked with the letter a to indicate its position in each of the figures . the upward pivoting of lifting arms 46 causes support plates 38 to raise . this initial movement , shown in fig4 b , raises food carrier 20 but does not rotate the food carrier since when star wheel 58 is in the position of fig4 b , cam pin 60 is just about to engage cam surface 64 . in the position of fig4 c , cam pin 60 has been engaged by cam surface 64 and cam pin 62 is just about to engage cam surface 66 . in the position of fig4 d , cam pin 62 has finished its engagement with cam surface 66 and cam pin 61 is engaging arm surface 68 to direct food carrier to the position of fig4 d , that is , at a second elevation and at a second rotary orientation , which is about 135 ° rotated from the rotary orientation of fig4 a . lowering support plates 38 by the downward pivotal movement of pivotal lifting arms 46 causes food carrier 20 to once again attain the position of fig4 a as the food carrier contacts the cooking surface of , for example , cooking vessel 8 . thus the final rotation of food carrier 20 from the position of fig4 d back to the position of fig4 a is caused by the food ( not shown ) and / or food carrier 20 resting against the cooking surface . to prevent reverse rotary rotation of food carrier 20 , a ratchet 70 is used on the opposite side of u - shaped frame from star wheel 58 . ratchet 70 includes a ratchet wheel 72 keyed to support shaft 52 and a pawl 74 pivotally mounted to support plate 38 . if desired , other types of anti - rotation devices , and sometimes even frictional resistance , can be used to prevent the reverse rotation of food carrier 20 . referring to fig3 and 3a , drive assembly 14 will be described . drive assembly 14 includes a drive cylinder 76 mounted for vertical movement within cylindrical coupler 28 . drive cylinder 76 includes a pair of wings 78 which pass through openings 80 formed in cylindrical coupler 28 . wings 78 are positioned to overlie the rounded proximal ends 82 of lifting arms 46 so that movement of drive cylinder 76 downwardly causes wings 78 to engage ends 82 thus pivoting arms 46 about pivots 48 thus raising support plates 38 . due to the short distances between pivots 48 and proximal ends 82 and the long distances between pivots 48 and slots 42 through which lifting arms 46 pass , a relatively short axial movement of drive cylinder 76 causes a relatively large lifting distance of support plates 38 . in the preferred embodiment movement of drive cylinder 76 , a distance of 0 . 35 &# 34 ; causes lifting arms 46 to move upwardly thus raising support plates 38 a distance of about 2 . 5 &# 34 ; to produce a lever arm advantage of about 7 to 1 . drive assembly 14 includes a gear box 84 housing a drive pulley 86 connected to a driven pulley 88 by a belt 90 . pulley 88 is keyed to a cylindrical driver 92 which is keyed to cylindrical coupler 28 . thus , rotating driven pulley 88 causes driver 92 , cylindrical coupler 28 and thus flipping assembly 4 to rotate as well . this aspect of rotating flipping assembly 4 and thus food carrier 20 is optional . flipping assembly 4 is supported in its vertical position by a bracket 93 which couples assembly 4 to the lower end of main shaft 94 . main shaft 94 is free to rotate within drive cylinder 76 and is supported at its upper end by gear box 84 through a clip or latch 96 . cylindrical driver 92 has a gear 98 keyed to it which drives a second gear 100 keyed to a gear shaft 102 . gear shaft 102 has a third gear 104 ; third gear 104 has a downwardly - facing circular cam surface 106 which engages a cylindrical tube 108 ; tube 108 is free to move axially within cylindrical driver 92 . the lower end of cylindrical tube 108 contacts the upper end of cylindrical driver 76 . as third gear 104 rotates , circular cam surface 106 pushes on the upper edge of cylindrical tube 108 forcing cylindrical tube 108 downwardly against the upper end of drive cylinder 76 , which also floats freely axially within cylindrical driver 92 . this downward movement of tube 108 and cylinder 76 is what causes proximal ends 82 to be driven downwardly thus raising distal ends 44 of lifting arms 46 . it should be noted in fig3 and 3a , there is a gap between drive cylinder 76 and proximal ends 82 and between the upper end of tube 108 and cam surface 106 for clarity of illustration . in practice these components will typically contact one another due to the weight of the various components . in use , a piece of food is mounted to food carrier 20 and the approximate settings are made to motor / controller housing 6 . at the appropriate time during cooking , gear 104 is rotated causing distal ends 44 of lifting arms 46 to pivot upwardly thus raising support plates 38 . doing so causes food carrier rotator assembly 21 to first raise and then raise and rotate food carrier 20 as the food carrier moves from the first elevation and first rotary orientation of fig4 a to the second elevation and second rotary orientation of fig4 d . the latter occurs when a high point of circular cam surface 106 engages the upper end of cylindrical tube 108 . due to the weight of lifting arms 46 , support plates 38 , rotator 21 and food carrier 20 , drive cylinder 76 and cylinder tube 108 tend to move upwardly . continued movement of gear 104 causes cam surface 106 to continue moving along cylinder tube 108 until a low point along circular cam surface 106 engages the cylindrical tube allowing distal ends 44 of arms 46 to drop thus permitting food carrier 20 and the food carrier therewith to once again rest against the cooking surface of cooking vessel 8 . fig5 illustrates an alternative embodiment of the invention with like reference numerals each referring to like structure . in this embodiment the particular lifting assembly used to raise lift shaft 120 and thus lifter 122 is not shown . the basic concept is the same as for the embodiment of fig1 - 4d and thus its operation will not be discussed in detail . however , cam pins 60 - 63 are at the same axial position ; to help accommodate engagement of cam pin 60 with surface 68 , cam pin 60 can pivot about 30 ° to prevent binding of cam pin 60 when lifter 122 is lowered . this problem is eliminated by the axial offset of cam pins 60 , 61 relative to cam pins 62 , 63 as in the embodiment of fig1 - 4d . the various components can be made from food grade materials , preferably stainless steel for most of the rigid structural components , suitable for use at the cooking temperatures and environment encountered . non - stick coatings can be used for certain surfaces , such as for covering aluminum surfaces , as well . appropriate fda - approved , high temperature plastics can be used if desired . other modifications and variations can be made to the disclosed embodiments without departing from the subject of the invention as defined in the following claims . for example , other lifting devices such as scissors lifting devices , rack and pinion lifting devices , chain and sprocket lifting devices , could be used instead of the pivot arms lifting device . rotator assembly 21 can be made from other rotary device assemblies such as rack and pinion assemblies , pulley / drive belt assemblies or worm / gear assemblies .
a food flipping assembly , used to automatically flip food 180 ° while cooking , includes a frame having cam - carrying u - shaped arms , and a pair of movable support plates slidably mounted to the u - shaped arms for movement between first and second elevations . a food carrier is pivotally mounted to the support plates for movement about a horizontal axis . a food carrier rotator is mounted to the food carrier and has drive elements which engage cam surfaces carried by the arms . movement of the food carrier from the first elevation to an intermediate elevation does not cause the food carrier to rotate ; movement from the intermediate elevation to the second elevation causes the drive elements to engage the cam surfaces thus rotating the food carrier about 135 °. lowering of the food carrier back onto the cooking surface causes the food carrier to complete its 180 ° rotation .