Torque limiting filter wrench

An oil filter socket having a torque limited maximum is provided. Namely, a torque limiting mechanism is provided interior a bore defined by a nut adapted to receive a conventional ratchet. The torque limiting mechanism includes a cam having bearing race notches formed circumferentially there-around. A plurality of ball bearings rest inside the notches until the rotational torque force applied to the socket from the ratchet overcomes the spring force acting opposite the cam.

CROSS REFERENCE TO RELATED APPLICATION

The present application claims priority from and the benefit of Canadian Patent Application No. 2,872,837 filed on Dec. 1, 2014, the entire contents of which is hereby incorporated herein by reference.

BACKGROUND

Technical Field

The present disclosure relates generally to the field of hand tools. More particularly, the present disclosure relates to a socket wrench or ratchet that includes an oil filter socket for removing an oil filter from an engine. Specifically, the present disclosure relates to a socket for a ratchet dimensioned to remove an oil filter canister from an engine, the socket having a torque limiting mechanism therein.

Background Information

A socket wrench is a type of wrench that has a socket attached at one end. Often the socket wrench operates in a ratcheting motion and may be referred to as a ratchet. A ratchet is a hand tool in which a metal handle is attached to a ratcheting mechanism, which attaches to a socket, which in turn fits onto a type of bolt or nut.

The ratchet is pulled or pushed in one direction by an operation. During movement, the ratchet loosens or tightens the bolt or nut attached to the socket. Turned the other direction, the ratchet does not turn the socket but allows the ratchet handle to be re-positioned for another turn while staying attached to the bolt or nut. This ratcheting action allows the fastener to be rapidly tightened or loosened in small increments without disconnecting the tool from the fastener.

Some ratchets may have a switch is built into the ratchet head that allows the user to apply the ratcheting action in either direction, as needed, to tighten or loosen a fastener.

Oil filters are generally screwed on to an engine. During the installation process a sufficient amount of torque is required for the oil filter to seal properly while an excessive amount of torque will make the oil filter difficult to remove or cause damage to the interfacing surfaces. Mechanics generally utilize a torque wrench in conjunction with an oil filter wrench/oil filter socket which requires multiple tools to perform the task and the latter results in a possible under or over torque condition.

SUMMARY

Issues continue to exists with the current types of oil filter wrenches and oil filter sockets utilized in conjunction with a torque wrench and heretofore, upon information and belief, an oil filter socket having a torque limiting mechanism therein has never been developed. The present disclosure addresses these and other issues.

In one aspect, the disclosure may provide an oil filter socket comprising: a first end spaced opposite a second end and a central axis extending therebetween; a cup including an edge defining an opening adjacent the first end and an inner surface extending axially towards a closed end, the inner surface defining a filter cavity sized to receive an oil filter therein; a nut adjacent the closed end exterior the cup and centered about the central axis, the nut defining a bore; and a torque limiting mechanism interior the bore centered about the central axis configured to selectively set a tightening torque maximum of the oil filter socket.

In another aspect, the disclosure may provide a torque limiting mechanism on an oil filter socket comprising: a plurality of ball bearings disposed within an axially aligned bore formed by a nut; a spring in the operatively connected to the plurality of ball bearings inside the bore; a set screw adjacent an end of the nut; a cam intermediate the plurality of ball bearings and the spring, the cam defining a plurality of circumferentially extending notches, wherein each notch is formed from two walls aligned at different incident angles relative to a central axis; and a socket rigidly connected to the nut sized to receive an oil filter bolt.

In another aspect, the disclosure may provide a method comprising the steps of: setting a torque maximum limit inside an oil filter socket; connecting the oil filter socket to one of (i) an oil filter canister, and (ii) an oil filter bolt head; and rotating the oil filter socket with a ratchet free of any torque limiting settings until the torque maximum limit inside the oil filter socket has been reached.

In another aspect, the disclosure may provide an oil filter socket having a torque limited maximum. Namely, a torque limiting mechanism is provided interior a bore defined by a nut adapted to receive a conventional ratchet. The torque limiting mechanism includes a cam having bearing race notches formed circumferentially there-around. A plurality of ball bearings rest inside the notches until the rotational torque force applied to the socket from the ratchet overcomes the spring force acting opposite the cam.

DETAILED DESCRIPTION

As depicted inFIG. 1, a torque limiting filter wrench system100includes a socket wrench or ratchet102, a drive extension16, and an oil filter socket5having a torque limiting clutch mechanism6therein.

As depicted inFIG. 2throughFIG. 4, oil filter socket5includes a first end22opposite a second end24centered about a central axis20extending therebetween. Oil filter socket5includes a cup10, a nut12, a cam13, a spring14, a threaded disc15, a square hole17defined by cam13, a plurality of following ball bearings18, and set screws19.

Cup10include an annular edge26at first end22defining an opening to an oil filter chamber28defined by an inner surface of cup10. Cup10further includes a closed end30offset from first end22having apertures therein threadedly receiving set screws19.

Nut12is rigidly connected to cup10and is offset towards the second end24from cup10adjacent closed end30and centered about central axis20. Nut12defines a bore32where some components of torque limiting clutch mechanism6are retained.

Within bore32, annular spring member14is centered axially along central axis20interior the inner surface of nut12intermediate the threaded adjustment member15and cam13.

A plurality of ball bearings18are positioned around central axis20in an equally spaced manner intermediate cam13and set screws19. Ball bearings18have an upper portion34that is closer to first end22than a cam end36that faces the same direction as upper portion34. Cam13further includes circumferential outer edge38that is radially closer to central axis20than a tangential outer edge40of ball bearing18. Cam13defines square hole17which is configured to releasably mate with a foremost end42of extension16releasably coupled to ratchet102.

With continued reference toFIG. 2throughFIG. 4, the set screws19are equal to the number of ball bearings18retained within bore32of nut12. In the shown example, there are two ball bearings18and two associated set screws19respectively coupled therewith. In the embodiment depicted inFIG. 2throughFIG. 4, set screws19are threadedly adjustable through apertures formed in cup10adjacent closed end30inside oil filter chamber28as is depicted in the bottom plan views ofFIG. 6andFIG. 7. Note that the bottom plan views ofFIG. 6andFIG. 7depict two set screws but there could be any number of plurality of set screws, each associated with the ball bearings18and as stated above, and in one particular embodiment includes three set screws respectively coupled with three ball bearings.

Alternatively, another embodiment may reverse the torque limiting clutch mechanism6within a bore32of nut12as is depicted inFIG. 5wherein the set screws19are adjustable by extending through nut12which requires threaded disc15to extend towards first end22adjacent closed end30of cup10.

As depicted inFIG. 6andFIG. 7, the bottom plan views of alternate embodiments of cup10are provided to show that the interior chamber28may be formed of different geometric configurations depending on the type of oil filter11that needs to be tightened or loosened through the use of system100.

As depicted inFIG. 9throughFIG. 18, an additional exemplary embodiment of the present disclosure may include portions of the torque limiting clutch mechanism6interior to a socket50formed with nut12directly connected in a rigid manner to an cylindrical housing52forming a ledge54at the rigid connection between the two. With this version, cup10is not shown but may be attached and extend away from ledge54in a manner as one having ordinary skill in the art would understand in order to grasp an oil filter therein.

As depicted inFIG. 12, the three set screws19are each associated with the plurality of ball bearings18inside a bore56of socket50. In this embodiment, spring14is a sprig formed from belleville washers applying force against a cam60.

As depicted inFIG. 13throughFIG. 15, a cam60includes a first end62opposite a second end64and a cylindrical sidewall66extending therebetween. Cam60forms a plurality of circumferentially extending notches68configured to receive ball bearings18therein in an assembled state. Each notch68is formed of two side walls. Namely, a first sidewall70which slopes up to a top72at first end62at a first incident angle74. A second sidewall75extends upwardly towards an upper terminal end73at a second incident angle76. Second incident angle76is different than the first incident angle74. First incident angle74is smaller than second incident angle76. First incident angle74is associated with counterclockwise rotation of socket50and the second incident angle is associated with clockwise rotation of socket50. The clockwise rotation is identified as arrow CW inFIG. 15and the counterclockwise rotation is identified by arrow CCW inFIG. 15. The first incident angle74associated with a counterclockwise rotation is smaller relative to central axis20which increases the torque setting for loosening rotation of attaching oil filter11to an engine block. The purpose of the narrower first incident angle74is to allow for a greater torque to be applied during the loosening process as the ratchet and the device is turned in the counterclockwise direction. In one particular embodiment, the torque limit for the loosening direction is in a range from about 20% to about 40% greater than that of the maximum torque limit for tightening the oil filter.

In accordance with an aspect of the present disclosure, oil filter socket5and oil filter socket50each provide embodiments designed to be used with a process for both installing and removing an oil filter11from an engine with the torque limiting clutch mechanism6contained in either socket5or socket50. Each socket5,50of the present disclosure addresses the heretofore need for a simpler device to correctively install an oil filter to an engine with the proper amount of torque such that excessive tightening or a loose fitting oil filter does not occur.

In one exemplary embodiment, oil filter11has an outer canister diameter in a range from about 60 mm to about 120 mm. Inner chamber28of cup10is sized to complementarily receive an oil filter therein thus also having a diameter in a range from about 60 mm to 120 mm. Additionally, chamber28may have a depth close to one third that of the outer diameter of cup10. So, for example, if cup10has an outer diameter of 3 inches, then the axially aligned depth of chamber28would be about one inch. The depth of chamber28is determined by the axial length of the inner surface defining the inner chamber which is purposefully greater than oil filter cap wrenches that have large outer diameters and narrow depths of filter chambers.

In operation, an operator grasps ratchet102and releasably attaches drive extension16thereto. The terminal end42of drive extension16is inserted through bore32on nut12of filter socket5such that the squared end nests within square hole17formed in cam13. Alternatively, in the oil filter socket50embodiment, drive extension16may be inserted through cam60into squared hole17. Ratchet102can rotate about central axis20in a tightening manner in a clockwise direction.

Prior to the step of tightening socket5, a user may selectively set the set screws19to a desired maximum torque associated with the torque necessary to attach oil filter11to an engine block without over tightening the components together. The set screws selectively set at the maximum torque contact ball bearings18against cam13thereby applying forcible pressure against spring14.

As ratchet102is rotated about central axis20in the clockwise direction, a reciprocal force is applied to socket5from the threading of oil filter11to the engine block. When the reciprocal force of the threading of oil filter11overcomes the set maximum force determined by the set screws application of pressure against spring14, the ball bearings slide over detents on the set screws such that socket5gives way and cannot over tighten oil filter11to the engine block.

The oil filter socket50embodiment depicted inFIG. 9may be releasably attached to a ratchet102and the socket portion may be releasably attached to the molded nut on a drop in filter canister attached to a combustion engine.

Prior to the step of attaching socket50to the nut on the oil filter canister, an operator selectively sets the screws to a maximum torque limit. Then, as depicted inFIG. 17andFIG. 18, a user may rotate the socket50in either the clockwise or counterclockwise direction. When rotating in the clockwise direction, ball bearing18nests within notch68. When the torque limit exceeds the compression force of spring14, spring14is collapsed in the direction of arrow C thereby allowing the cam to rotate such that ball bearing18travels upwardly along first wall70towards end73. In the compressed position ofFIG. 18, socket50can no longer apply rotational tightening force to the oil filter. Cam60will continue to rotate until a ball bearing18slides down second wall75into an adjacent notch68. When loosening the oil filter, ball bearing18will slide along second wall75in the counterclockwise direction. The compressed spring14will move in the axial direction identified by arrow C.

Moreover, the description and illustration of the disclosure are an example and the disclosure is not limited to the exact details described.