Machine jacks with a propping mechanism
The present invention is machine jacks having a propping mechanism comprised of a prop attached parallel to and jointly movable with the lifting arm, a storage well for receiving the prop in a retracted position, and a pin engagable with the prop to bias the prop and the body of the jack to prevent untimely lifting arm retraction.
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1. Machine jacks comprising: a jack housing, a lifting arm, and a prop; said housing having an upper surface; said lifting arm attached to said housing; said lifting arm having a center axis; said prop being elongated and oriented generally parallel with, and adjacent to, said lifting arm; said lifting arm and said prop jointly movable along said lifting arm center axis; said lifting arm and said prop controllably extendable away from and retractable toward said housing upper surface; said prop having at least one pin receptacle adjacent to said lifting arm; and a pin selectively engagable with said at least one pin receptacle such that restrictive motion of said prop biases an engaged said pin between said upper surface and an engaged said at least one pin receptacle.
The machine jacks further comprising: said housing having a storage well for receiving said prop.
Machine jacks comprising: a jack housing, a lifting arm, and a prop; said housing having an upper surface; said lifting arm attached to said housing; said lifting arm having a centre axis; said prop attached to said lifting arm distal said jack housing; said prop being elongated and oriented generally parallel with, and adjacent to, said lifting arm; said lifting arm and said prop jointly controllably extendable away from and retractable toward said housing upper surface along said lifting arm centre axis; said prop having at least one pin receptacle; and a pin selectively engagable with said at least one pin receptacle such that restrictive motion of said prop biases an engaged said pin between said upper surface and an engaged said at least one pin receptacle.
The machine jacks wherein: said at least one pin receptacle being a transverse perforation in said prop.
The machine jacks wherein: said lifting arm telescopically attached to said housing; and said lifting arm extendable outwardly from said upper surface.
Machine jacks having a jacking mechanism, a jack base, a jack hot using, and a lifting arm, said safety jack comprising: said jack housing having a bottom and a top; said machine jack base attached to said jack housing bottom; said lifting arm having a centre axis; said lifting arm telescopically attached to said jack housing; a prop; said prop attached to said lifting arm distal said jack housing; said jacking mechanism having a lifting operation and a lowering operation, each consisting of movement along said lifting arm centre axis; said lifting arm and said prop jointly extendable outwardly from said jack housing top in said lifting operation; said lifting arm and said prop jointly retractable inwardly toward said jack housing top in said lowering operation; said housing having a storage well for receiving said prop; a pin; said prop having at least one pin receptacle for selectively receiving said pin; and each said pin receptacle configured to bias a selectively received said pin against said jack housing top in order to selectively disable said lowering operation.
A great variety of machine jacks are known in the field. Machine jacks are employed to lift items of substantial weight to include vehicles. In some instances, once an item is lifted it may be desired to maintain the item in the elevated position for an extended period while activity is conducted about the item. In these instances, there exists a hazard that the particular jack may lose lifting force engagement, permitting the weighty item to unexpectedly lower. This presents a particularly serious hazard to activity being conducted underneath the item. For this reason the field of art practices placing rigid supports or jack stands under items to prevent the item from lowering in case the jack loses lifting force.
The prior art possesses a variety of exemplary adjustable jacks and jack stands. The following are a few examples.
A machine jacks stand with a safety-locking device whereby a pin is positioned through a plurality of alienable corresponding holes in the shaft and the housing locking these members with respect to each other longitudinally. The pin is keyed so as to prevent withdrawal of the pin until rotated into an aligned position.
A jackable stand comprising of a vertical post that projects upward normal to a base. A carriage is attached to the vertical post moveably along the length of the post. The post has receiver holes vertically spaced apart along a length of the post and extending through the post. The carriage and base are engageable by a jack that may employ mechanical advantage to progress the carriage along the length of the post. A pin is employed in a selected receiver hole to restrict movement of the carriage along the post.
Machine jacks stand having a hydraulic bottle jack positionable on an elongated jack support comprising a tubular outer housing, a moveable cylindrical member, and a pin. The outer housing has a pin anchor receiver, such that the pin may be inserted through the outer housing. The moveable member has a plurality of receiver holes vertically spaced apart along a length that, with the moveable member inserted into the outer housing, may be selectively alignable with the anchor receiver such that the pin may be inserted through both a receiver hole and the anchor hole, fixing the outer housing and moveable member longitudinally.
A cabinet installation lifting system comprising a machine jack and a pair of extendable supports, wherein said supports each comprise a tubular outer housing having an pin anchor receiver, a moveable cylindrical member having a plurality of receiver holes vertically spaced apart along a length that, with the moveable member inserted into the outer housing, may be selectively alignable with the anchor receiver such that a pin may be inserted through both a receiver hole and the anchor hole, fixing the outer housing and moveable member longitudinally throughout the lifting range of the jack.
An adjustable machine jacks stand having a ratchet and pawl height maintenance mechanism with a pin and hole mechanism wherein the holes in the post coordinate with the teeth in the post so that any engagement between the pawl and a tooth ensures that a pair of holes in the base and the post are aligned to receive a pin.
It would be an improvement to the art to provide a machine jack having a locking mechanism comprised of a prop exterior to the lifting arm, a storage well for receiving the prop in a retracted position, and a locking pin engagable with said prop to bias said prop and the body of the jack to selectively prevent lifting arm retraction.
The invention is a machine jack having a housing, a lifting arm or ram, and a prop. The prop may comprise at least one segment extending from said bottle housing parallel with said ram. Another embodiment of a prop may be integrated into a lifting arm. The bottle housing comprises a storage area designed to receive the prop from the face from which the ram extends. A suitable storage area may comprise a well positioned around the circumference of the ram, having a width and depth suitable to receive the prop as the prop moves with the ram from an extended position primarily out of the well to a retracted position primarily contained in the well. The prop comprises at least one pin receptacle for engagement with a pin such that the engagement of said pin with said receptacle positions said pin to restrict retraction of said ram to within said housing by biasing between the engaged pin receptacle and the bottle housing adjacent to the outer edge of the well. In this manner such an inventive hydraulic jack may mechanically support a weight in an extended position, even if said machine jacks were to lose hydraulic support of said ram.
The machine jacks 10 is shown. Machine jacks 10 may be a hydraulic bottle jack having a generally cylindrical jack housing 12 fixedly attached to a solid jack base 18 at one end, generally considered the bottom of jack 10. Other types of jacks known in the art may employ the inventive device. In the exemplary embodiment, jacking mechanism 16 is adjacent and operable linked to jack housing 12. Operation of jacking mechanism 16 creates hydraulic pressure from mechanical leverage through hydraulic fluid (not shown) within a fluid reservoir 24 contained in jack housing 12; a device and process known to the art. Also known to the art is the employment of this pressurized hydraulic fluid to work against the one end of ram 14 recessed into jack housing 12 causing ram 14 to controllably extend away from and retract toward jack housing 12 with substantial force F having substantial lifting capacity. In this fashion ram 14 may be described as being telescopically attached to jack housing 12. A jack shoe 17 is provided on the opposite end of ram 14 from machine jack housing 12, generally considered the top of jack 10, to provide an interface surface to an item to be jacked (not shown), as known in the art.