CENTERING TOOL
United States Patent 3836277
A work object centering tool having a socket mount with a conical exterior surface defining a longitudinal axis, an elongated rod secured on the mount in alignment with the axis, a slide member received on the rod, three arms pivotally secured on the slide member, an extension individually borne by each arm in substantial right angular relation thereto, and springs interconnecting the arms tensionably to retain the arms in contact with the surface of the mount over a predetermined path of movement with the remote ends of the extensions in a plane substantially normal to the axis of the mount and approximately 120° apart in the plane.
US Patent References:
Centering device for boring and grinding machines
Appleton - November 1929 - 1734787
Center locator
Mahl - May 1967 - 3318010
CENTERING ATTACHMENT FOR CYLINDER-BORING DEVICE
Holleman - December 1971 - 3630632
Centering device for boring and grinding machines
Appleton - November 1929 - 1734787
Center locator
Mahl - May 1967 - 3318010
CENTERING ATTACHMENT FOR CYLINDER-BORING DEVICE
Holleman - December 1971 - 3630632
Application Number:
05/366865
Publication Date:
09/17/1974
Filing Date:
06/04/1973
View Patent Images:
Export Citation:
Assignee:
Porta-Tool, Incorporated (Clovis, CA)
Primary Class:
Other Classes:
408/82, 33/644
International Classes:
B23Q17/22; B23B49/00
Field of Search:
408/75,82 33/185R,191
Primary Examiner:
Husar, Francis S.
Attorney, Agent or Firm:
Huebner & Worrel
Claims:
Having described my invention, what I claim as new and desire to secure by Letters Patent is
1. A tool for positioning a work object, having an axis, with said axis disposed in a predetermined attitude with respect to a reference member, the tool comprising an elongated rod having opposite ends; a mount, having a cam surface and a reference member engaging socket defining an axis, secured on one end of the rod; a slide member received on the rod; at least three angled arms pivotally suspended from the slide member toward the mount; said arms being mounted for movement in planes laterally disposed with respect to the rod, said planes intersecting in coincidence with the axis of the socket; and means for resiliently retaining the arms in engagement with the cam surface.
2. The tool of claim 1 in which each arm has a control portion, having opposite ends, pivotally secured on the slide member at one of its ends and mounting a lateral extension at the other of its ends.
3. The tool of claim 2 in which the resilient means includes tension spring interconnecting the arms.
4. The tool of claim 3 in which a handle is borne by the rod on the end thereof remote from the mount, said handle having a striking surface facing the slide member.
5. A tool for centering the cylindrical bore of an internal combustion engine cylinder relative to the work end of a boring machine, the tool comprising a releasible mount defining a longitudinal axis, said mount having a work end receiving socket and a conical exterior surface in axial alignment with the longitudinal axis; an elongated rod secured on the mount remote from the socket and in axial alignment therewith; a handle affixed on the end of the rod remote from the mount; a substantially cylindrical slide member received on the rod intermediate the mount and the handle; three pivotal connections mounted on the slide member defining a plane substantially normal to the rod, the connections being spaced approximately 120° in said plane equidistant from the rod; an arm individually fastened on each connection; an extension borne by each arm remote from its respective connection in right angular relation thereto; and tension springs interconnecting the arms to urge them toward the axis of the mount.
6. A tool for centering a cylinder concentrically about a predetermined axis comprising means for supporting the cylinder for adjustable movement relative to the axis while constraining the cylinder to parallelism therewith, a cone mounted concentrically of the axis, a carrier mounted for reciprocal movement along the axis toward and from the cone, substantially identical arms pivotally mounted on the carrier in substantially equally spaced relation about the axis for movement inwardly toward the axis and outwardly therefrom having portions engageable with the cone and fingers outwardly extended for engagement with the cylinder, and resilient means urging the fingers inwardly toward the axis whereby movement of the arms endwardly of the cone correspondingly extends and retracts the fingers to and from cylinder engagement.
7. A tool for centering a cylinder concentrically about a predetermined axis comprising means for supporting the cylinder in a plane normal to the axis for adjustable movement in the plane with the cylinder parallel to said axis, a rod, means mounting the rod in alignment with the axis, a cone mounted concentrically of the axis, a carrier mounted on the rod for reciprocal movement toward and from the cone, at least three substantially identical arms pivotally mounted on the carrier in substantially equally spaced relation about the rod for movement inwardly toward the axis and outwardly therefrom having portions engageable with the cone and fingers outwardly extended for engagement with the cylinder, and resilient means urging the fingers inwardly toward the axis whereby movement of the carrier toward the cone slides the arms endwardly thereover correspondingly pivoting the arms outwardly to bring the fingers into positioning engagement with the cylinder.
1. A tool for positioning a work object, having an axis, with said axis disposed in a predetermined attitude with respect to a reference member, the tool comprising an elongated rod having opposite ends; a mount, having a cam surface and a reference member engaging socket defining an axis, secured on one end of the rod; a slide member received on the rod; at least three angled arms pivotally suspended from the slide member toward the mount; said arms being mounted for movement in planes laterally disposed with respect to the rod, said planes intersecting in coincidence with the axis of the socket; and means for resiliently retaining the arms in engagement with the cam surface.
2. The tool of claim 1 in which each arm has a control portion, having opposite ends, pivotally secured on the slide member at one of its ends and mounting a lateral extension at the other of its ends.
3. The tool of claim 2 in which the resilient means includes tension spring interconnecting the arms.
4. The tool of claim 3 in which a handle is borne by the rod on the end thereof remote from the mount, said handle having a striking surface facing the slide member.
5. A tool for centering the cylindrical bore of an internal combustion engine cylinder relative to the work end of a boring machine, the tool comprising a releasible mount defining a longitudinal axis, said mount having a work end receiving socket and a conical exterior surface in axial alignment with the longitudinal axis; an elongated rod secured on the mount remote from the socket and in axial alignment therewith; a handle affixed on the end of the rod remote from the mount; a substantially cylindrical slide member received on the rod intermediate the mount and the handle; three pivotal connections mounted on the slide member defining a plane substantially normal to the rod, the connections being spaced approximately 120° in said plane equidistant from the rod; an arm individually fastened on each connection; an extension borne by each arm remote from its respective connection in right angular relation thereto; and tension springs interconnecting the arms to urge them toward the axis of the mount.
6. A tool for centering a cylinder concentrically about a predetermined axis comprising means for supporting the cylinder for adjustable movement relative to the axis while constraining the cylinder to parallelism therewith, a cone mounted concentrically of the axis, a carrier mounted for reciprocal movement along the axis toward and from the cone, substantially identical arms pivotally mounted on the carrier in substantially equally spaced relation about the axis for movement inwardly toward the axis and outwardly therefrom having portions engageable with the cone and fingers outwardly extended for engagement with the cylinder, and resilient means urging the fingers inwardly toward the axis whereby movement of the arms endwardly of the cone correspondingly extends and retracts the fingers to and from cylinder engagement.
7. A tool for centering a cylinder concentrically about a predetermined axis comprising means for supporting the cylinder in a plane normal to the axis for adjustable movement in the plane with the cylinder parallel to said axis, a rod, means mounting the rod in alignment with the axis, a cone mounted concentrically of the axis, a carrier mounted on the rod for reciprocal movement toward and from the cone, at least three substantially identical arms pivotally mounted on the carrier in substantially equally spaced relation about the rod for movement inwardly toward the axis and outwardly therefrom having portions engageable with the cone and fingers outwardly extended for engagement with the cylinder, and resilient means urging the fingers inwardly toward the axis whereby movement of the carrier toward the cone slides the arms endwardly thereover correspondingly pivoting the arms outwardly to bring the fingers into positioning engagement with the cylinder.
Description:
BACKGROUND OF THE INVENTION
The present invention relates to a centering tool and more particularly to such a tool which permits immediate and precise centering of a cylindrical bore with respect to a selected reference point. The tool is adapted for use with the applicant's invention disclosed in his patent application entitled "Boring Machine" submitted concurrently herewith.
Centering tools have long been employed in industry to center a work object, such as an internal combustion engine cylinder, relative to a work performing tool, such as a boring machine. As in the case of refinishing the cylindrical bore of an engine cylinder, precision within quite narrow tolerances is essential in order to produce a finished product of usable quality. For this reason, prior art centering tools are commonly of relatively complex construction requiring rather involved and time consuming manipulation in order to insure the required precision. The delay attendant with such manipulation of the centering tools makes their use onerous and expensive, but nonetheless essential.
An additional deficiency encountered with the use of conventional centering tools is directly related to their relatively complex construction. After long periods of use, such centering tools begin to lose the precision with which they can be employed. Particularly where screw threaded adjustments, slide adjustments and the like are utilized, a certain degree of give or play begins imperceptively to develop in such structures after prolonged use. Since such play develops quite slowly, it may not be noticed until well after adverse results are produced.
Therefore, it has long been recognized that it would be desirable to have a centering tool which is of extremely simplified construction affording an ease of operation unattainable with conventional centering tools and which can be employed with dispatch to center a work object relative to a work performing tool within quite narrow and acceptable tolerances insuring a long operational life without danger of progressive variation in the results produced.
SUMMARY OF THE INVENTION
In view of the foregoing, it is an object of the present invention to provide an improved centering tool.
Another object is to provide such a tool which is of extremely simplified construction.
Another object is to provide such a tool which can rapidly be mounted, operated to center the work object relative to the work performing tool, and removed without onerous and time-consuming adjustment.
Another object is to provide such a tool which has a structure which minimizes the danger of the development of precision reducing play in the operative elements thereof.
Another object is to provide such a tool which is specifically adapted to center the cylindrical bore of an internal combustion engine cylinder with respect to the work end of a boring machine.
Another object is to provide such a tool which is adapted for use with the applicant's boring machine for which a patent has been applied.
A further object is to provide such a tool which is of minimum expense to manufacture and therefore to purchase.
Still further objects and advantages are to provide improved elements and arrangements therefore in a device for the purposes described which is dependable, economical, durable and fully effective in accomplishing its intended purposes.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a side elevation of the centering tool of the present invention shown mounted on the work end of a boring machine in centering relation to an engine cylinder.
FIG. 2 is a somewhat enlarged side elevation of the centering tool with portions thereof broken away to expose the interior construction thereof.
FIG. 3 is a horizontal section taken from a position indicated by line 3--3 in FIG. 2.
FIG. 4 is a horizontal section taken from a position indicated by line 4--4 in FIG. 2.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring more particularly to the drawing, the orienting or centering tool of the present invention is generally indicated by the numeral 10. The centering tool is adapted to be employed on a wide variety of types of work performing tools. However, as shown in FIG. 1 the centering tool is mounted on a boring machine, generally indicated by the numeral 11, disclosed in the applicant's patent application entitled "Boring Machine" submitted concurrently herewith. As disclosed in that application, the boring machine has a horizontal base plate 12 mounting a shaft bearing 13 therein. A tool mounting shaft 14 is received in the bearing for rotational and endward movement. The shaft has a work end 15 in which is laterally adjustably received a boring tool 16 having a cutting edge 17. A reference point in the form of a frustoconical projection 18 is affixed on the work end of the shaft in alignment with the axis of rotation of the shaft. A cylinder support plate 19 is secured on the base plate and has a recess 20 therein of a predetermined size concentric to the shaft. A pair of slide plates 21 are adjustably secured on the support plate for individual movement to and from the recess. A pressure applying plate 22, fragmentarily shown in FIG. 1, is borne by the machine for vertical movement to and from the slide plates. The pressure applying plate has a recess 23 which is positionable with the plate in approximate vertical alignment with recess 20.
An internal combustion engine cylinder is generally indicated at 30 in FIG. 1 shown in position for boring on the boring machine 11. The cylinder has a head end 31 and an opposite block end 32. The cylinder has a peripheral seat 33 adjacent to the head end and a peripheral seat 34 adjacent to the block end. The cylinder also has an interior cylindrical surface 35 defining a cylindrical bore 36 extending longitudinally through the cylinder to communicate with the opposite ends thereof.
The centering tool 10 has a cone or releasible mount 40, preferably constructed of hardened steel, having a frustoconical cam surface 41 and defining a longitudinal axis indicated at 42 for illustrative convenience. The mount has a broad end 43 and an opposite narrow end 44. The peripheral juncture of the broad end and the cam surface preferably has a beveled edge 45, as shown in FIG. 1. A frustoconical bore or socket 46 extends inwardly of the mount from the broad end thereof in alignment with the longitudinal axis of the mount. The dimensions of the socket preferably precisely correspond to the dimensions of the projection 18 of the boring machine 11. Alternatively, the dimensions of the socket can be such as to permit pressure fitting of the socket about the projection. In any event, the size and shape of the socket are such that when the mount is received on the projection 18, the mount is securely retained in axial alignment with the axis of rotation of the shaft. It will, of course, be seen that the mount can similarly be employed to engage a similar structure of any work performing tool for performance of the centering operation. Furthermore, any suitable structure can be employed for connection of the centering tool to the particular work performing tool being employed without departing from the invention.
An elongated cylindrical rod 50, having opposite ends 51, is integrally mounted on the narrow end 44 of the releasible mount 40 by one of its ends in alignment with the longitudinal axis of the mount. A suitable handle 52 is affixed on the remote end of the rod. The handle is of a configuration presenting a striking surface 53 facing the mount at the opposite end of the rod.
A carrier or slide member 60, having a longitudinal cylindrical bore 61 of a diameter corresponding to that of the rod 50, is slidably received on the rod so that the rod extends through the cylindrical bore thus permitting movement of the member along the rod between the striking surface 53 of the handle 52 and the narrow end 44 of the mount 40. The slide member has a striking end 62 most closely adjacent to the striking surface of the handle and an opposite flange portion 63 most closely adjacent to the mount. The flange portion extends outwardly of the slide member substantially normal to the rod. The slide member, intermediate its striking end and flange portion, preferably has a roughened cylindrical surface 64.
As perhaps best shown in FIG. 3, three pivotal connections are borne by the flange portion 63 of the slide member 60 and are generally indicated by numerals 70. Each of the pivotal connections has a slot 71 extending through the peripheral flange 63 and communicating with the cylindrical bore 61, as shown in FIG. 2. As shown in FIG. 4 for illustrative convenience, the slots individually define longitudinal, central planes 72 which intersect in coincidence with the longitudinal axis 42 of the releasible mount 40. The planes radiate from the longitudinal axis spaced 120° apart, as shown therein. Each of the pivotal connections has a counterbore 73 extending into the flange portion of the slide member in tangentially spaced relation to the rod 50 and extending through its respective slot normal to the central plane thereof. Each counterbore has a screw threaded portion 74 adjacent to its innermost end. A screw threaded pivot pin 75 is individually received in each of the bores and screw threadably engaged in the threaded portion 74 of the bore.
An arm 80 is individually, pivotally mounted on the pivot pin 75 of each pivotal connection 70. Each arm has a control portion 81, having opposite ends 82, pivotally mounted on its respective pivot pin adjacent to one of its opposite ends, as shown in FIG. 2. A finger or lateral extension 83 is mounted on the other end of each arm extending outwardly from and substantially normal to the rod. Each extension has a contact point 84. The end of the control portion of each arm mounting the extension has a cam edge 85 opposite to the extension. The arms are identical so that the control portions of the arms are the same length and configuration and the distances between the cam edges and the contact points of the arms are identical. The control portions of the arms are interconnected by tension springs 86, as best shown in FIG. 4. The tension springs resiliently maintain the cam edges of the arms in engagement with the mount 40 or rod 50 depending upon the position of the slide member 60.
OPERATION
The operation of the described embodiment of the subject invention is believed to be clearly apparent and is briefly summarized at this point. As described in greater detail in the applicant's previously identified patent application on the boring machine 11, rough positioning of the engine cylinder 30 on the machine is readily accomplished. The work end 15 mounting the boring tool 16 is retracted to the position shown in FIG. 1. The slide plates 21 are loosened and positioned so as to permit receipt of the block end 32 of the cylinder therebetween with the peripheral seat 34 received gravitationally against the slide plates. The pressure applying plate 22 is pivoted downwardly to engage the peripheral seat 33 adjacent to the head end of the cylinder.
Subsequently, the centering tool 10, being held by the handle 52 and with the slide member 60 retracted to the position shown in FIG. 2, is inserted through the recess 23 of the pressure applying plate 22 and into the cylindrical bore 36 of the cylinder 30. The tool is directed so that the projection 18 of the shaft 14 is received in the frustoconical socket 46 of the releasible mount 40 and firmly seated therein, as shown in FIG. 1. Thus, the longitudinal axis 42 of the releasible mount and therefore of the elongated cylindrical rod 50 is precisely axially aligned with the axis of rotation of the shaft, as previously described.
The slide member 60 is then grasped by its roughened cylindrical surface 64 and directed toward the releasible mount. As the cam edges 85 of the arms 80 contact the mount 40, they are directed outwardly along the frustoconical cam surface 41 of the mount with the tension springs 86 maintaining the cam edges resiliently in contact with the cam surface. As the slide member continues to be motivated along the rod in the direction of the mount, the arms are forced away from the longitudinal axis 42 of the mount so that the contact points 84 of the lateral extensions 83 are similarly directed outwardly. Assuming the cylindrical bore 36 is not already accurately centered, one or two of the contact points engage the cylindrical surface 35 as movement of the slide member is continued. During continuation of the movement, the contact points engaging the surface move the cylinder 30 in that direction until the contact points of all three arms engage the cylindrical surface. When this occurs the slide member is thereby restrained from further movement toward the mount and the operator is thus informed that the cylindrical bore 36 is positioned in precise axial alignment with the longitudinal axis of the mount and therefore the axis of rotation of the shaft.
The slide plates 21 of the boring machine 11 are then motivated toward each other to engage the cylinder 30 and are then locked in position so as to retain the cylindrical bore 36 in the precisely centered position. The centering tool is removed from the projection 18 either by directly pulling upwardly on the handle 52 or, particularly where the fit on the projection is snug, by grasping the slide member 60 and motivating it toward the handle until the striking end 62 of the member strikes the striking surface 53 of the handle. The resultant jolt is sufficient to release the mount 40 from the projection and allow the tool to be withdrawn from the cylinder. This method of removal also allows the contact points 84 to be retracted from the cylindrical surface 35 of the cylinder so as to avoid scoring during removal.
Therefore, the centering tool of the present invention is of a simplified and reliable construction not heretofore achieved in conventional centering tools thus maximizing the ease and speed with which the tool can be operated while minimizing the risk of error in the results produced.
Although the invention has been herein shown and described in what is conceived to be the most practical and preferred embodiment, it is recognized that departures may be made therefrom within the scope of the invention, which is not to be limited to the illustrative details disclosed.
The present invention relates to a centering tool and more particularly to such a tool which permits immediate and precise centering of a cylindrical bore with respect to a selected reference point. The tool is adapted for use with the applicant's invention disclosed in his patent application entitled "Boring Machine" submitted concurrently herewith.
Centering tools have long been employed in industry to center a work object, such as an internal combustion engine cylinder, relative to a work performing tool, such as a boring machine. As in the case of refinishing the cylindrical bore of an engine cylinder, precision within quite narrow tolerances is essential in order to produce a finished product of usable quality. For this reason, prior art centering tools are commonly of relatively complex construction requiring rather involved and time consuming manipulation in order to insure the required precision. The delay attendant with such manipulation of the centering tools makes their use onerous and expensive, but nonetheless essential.
An additional deficiency encountered with the use of conventional centering tools is directly related to their relatively complex construction. After long periods of use, such centering tools begin to lose the precision with which they can be employed. Particularly where screw threaded adjustments, slide adjustments and the like are utilized, a certain degree of give or play begins imperceptively to develop in such structures after prolonged use. Since such play develops quite slowly, it may not be noticed until well after adverse results are produced.
Therefore, it has long been recognized that it would be desirable to have a centering tool which is of extremely simplified construction affording an ease of operation unattainable with conventional centering tools and which can be employed with dispatch to center a work object relative to a work performing tool within quite narrow and acceptable tolerances insuring a long operational life without danger of progressive variation in the results produced.
SUMMARY OF THE INVENTION
In view of the foregoing, it is an object of the present invention to provide an improved centering tool.
Another object is to provide such a tool which is of extremely simplified construction.
Another object is to provide such a tool which can rapidly be mounted, operated to center the work object relative to the work performing tool, and removed without onerous and time-consuming adjustment.
Another object is to provide such a tool which has a structure which minimizes the danger of the development of precision reducing play in the operative elements thereof.
Another object is to provide such a tool which is specifically adapted to center the cylindrical bore of an internal combustion engine cylinder with respect to the work end of a boring machine.
Another object is to provide such a tool which is adapted for use with the applicant's boring machine for which a patent has been applied.
A further object is to provide such a tool which is of minimum expense to manufacture and therefore to purchase.
Still further objects and advantages are to provide improved elements and arrangements therefore in a device for the purposes described which is dependable, economical, durable and fully effective in accomplishing its intended purposes.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a side elevation of the centering tool of the present invention shown mounted on the work end of a boring machine in centering relation to an engine cylinder.
FIG. 2 is a somewhat enlarged side elevation of the centering tool with portions thereof broken away to expose the interior construction thereof.
FIG. 3 is a horizontal section taken from a position indicated by line 3--3 in FIG. 2.
FIG. 4 is a horizontal section taken from a position indicated by line 4--4 in FIG. 2.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring more particularly to the drawing, the orienting or centering tool of the present invention is generally indicated by the numeral 10. The centering tool is adapted to be employed on a wide variety of types of work performing tools. However, as shown in FIG. 1 the centering tool is mounted on a boring machine, generally indicated by the numeral 11, disclosed in the applicant's patent application entitled "Boring Machine" submitted concurrently herewith. As disclosed in that application, the boring machine has a horizontal base plate 12 mounting a shaft bearing 13 therein. A tool mounting shaft 14 is received in the bearing for rotational and endward movement. The shaft has a work end 15 in which is laterally adjustably received a boring tool 16 having a cutting edge 17. A reference point in the form of a frustoconical projection 18 is affixed on the work end of the shaft in alignment with the axis of rotation of the shaft. A cylinder support plate 19 is secured on the base plate and has a recess 20 therein of a predetermined size concentric to the shaft. A pair of slide plates 21 are adjustably secured on the support plate for individual movement to and from the recess. A pressure applying plate 22, fragmentarily shown in FIG. 1, is borne by the machine for vertical movement to and from the slide plates. The pressure applying plate has a recess 23 which is positionable with the plate in approximate vertical alignment with recess 20.
An internal combustion engine cylinder is generally indicated at 30 in FIG. 1 shown in position for boring on the boring machine 11. The cylinder has a head end 31 and an opposite block end 32. The cylinder has a peripheral seat 33 adjacent to the head end and a peripheral seat 34 adjacent to the block end. The cylinder also has an interior cylindrical surface 35 defining a cylindrical bore 36 extending longitudinally through the cylinder to communicate with the opposite ends thereof.
The centering tool 10 has a cone or releasible mount 40, preferably constructed of hardened steel, having a frustoconical cam surface 41 and defining a longitudinal axis indicated at 42 for illustrative convenience. The mount has a broad end 43 and an opposite narrow end 44. The peripheral juncture of the broad end and the cam surface preferably has a beveled edge 45, as shown in FIG. 1. A frustoconical bore or socket 46 extends inwardly of the mount from the broad end thereof in alignment with the longitudinal axis of the mount. The dimensions of the socket preferably precisely correspond to the dimensions of the projection 18 of the boring machine 11. Alternatively, the dimensions of the socket can be such as to permit pressure fitting of the socket about the projection. In any event, the size and shape of the socket are such that when the mount is received on the projection 18, the mount is securely retained in axial alignment with the axis of rotation of the shaft. It will, of course, be seen that the mount can similarly be employed to engage a similar structure of any work performing tool for performance of the centering operation. Furthermore, any suitable structure can be employed for connection of the centering tool to the particular work performing tool being employed without departing from the invention.
An elongated cylindrical rod 50, having opposite ends 51, is integrally mounted on the narrow end 44 of the releasible mount 40 by one of its ends in alignment with the longitudinal axis of the mount. A suitable handle 52 is affixed on the remote end of the rod. The handle is of a configuration presenting a striking surface 53 facing the mount at the opposite end of the rod.
A carrier or slide member 60, having a longitudinal cylindrical bore 61 of a diameter corresponding to that of the rod 50, is slidably received on the rod so that the rod extends through the cylindrical bore thus permitting movement of the member along the rod between the striking surface 53 of the handle 52 and the narrow end 44 of the mount 40. The slide member has a striking end 62 most closely adjacent to the striking surface of the handle and an opposite flange portion 63 most closely adjacent to the mount. The flange portion extends outwardly of the slide member substantially normal to the rod. The slide member, intermediate its striking end and flange portion, preferably has a roughened cylindrical surface 64.
As perhaps best shown in FIG. 3, three pivotal connections are borne by the flange portion 63 of the slide member 60 and are generally indicated by numerals 70. Each of the pivotal connections has a slot 71 extending through the peripheral flange 63 and communicating with the cylindrical bore 61, as shown in FIG. 2. As shown in FIG. 4 for illustrative convenience, the slots individually define longitudinal, central planes 72 which intersect in coincidence with the longitudinal axis 42 of the releasible mount 40. The planes radiate from the longitudinal axis spaced 120° apart, as shown therein. Each of the pivotal connections has a counterbore 73 extending into the flange portion of the slide member in tangentially spaced relation to the rod 50 and extending through its respective slot normal to the central plane thereof. Each counterbore has a screw threaded portion 74 adjacent to its innermost end. A screw threaded pivot pin 75 is individually received in each of the bores and screw threadably engaged in the threaded portion 74 of the bore.
An arm 80 is individually, pivotally mounted on the pivot pin 75 of each pivotal connection 70. Each arm has a control portion 81, having opposite ends 82, pivotally mounted on its respective pivot pin adjacent to one of its opposite ends, as shown in FIG. 2. A finger or lateral extension 83 is mounted on the other end of each arm extending outwardly from and substantially normal to the rod. Each extension has a contact point 84. The end of the control portion of each arm mounting the extension has a cam edge 85 opposite to the extension. The arms are identical so that the control portions of the arms are the same length and configuration and the distances between the cam edges and the contact points of the arms are identical. The control portions of the arms are interconnected by tension springs 86, as best shown in FIG. 4. The tension springs resiliently maintain the cam edges of the arms in engagement with the mount 40 or rod 50 depending upon the position of the slide member 60.
OPERATION
The operation of the described embodiment of the subject invention is believed to be clearly apparent and is briefly summarized at this point. As described in greater detail in the applicant's previously identified patent application on the boring machine 11, rough positioning of the engine cylinder 30 on the machine is readily accomplished. The work end 15 mounting the boring tool 16 is retracted to the position shown in FIG. 1. The slide plates 21 are loosened and positioned so as to permit receipt of the block end 32 of the cylinder therebetween with the peripheral seat 34 received gravitationally against the slide plates. The pressure applying plate 22 is pivoted downwardly to engage the peripheral seat 33 adjacent to the head end of the cylinder.
Subsequently, the centering tool 10, being held by the handle 52 and with the slide member 60 retracted to the position shown in FIG. 2, is inserted through the recess 23 of the pressure applying plate 22 and into the cylindrical bore 36 of the cylinder 30. The tool is directed so that the projection 18 of the shaft 14 is received in the frustoconical socket 46 of the releasible mount 40 and firmly seated therein, as shown in FIG. 1. Thus, the longitudinal axis 42 of the releasible mount and therefore of the elongated cylindrical rod 50 is precisely axially aligned with the axis of rotation of the shaft, as previously described.
The slide member 60 is then grasped by its roughened cylindrical surface 64 and directed toward the releasible mount. As the cam edges 85 of the arms 80 contact the mount 40, they are directed outwardly along the frustoconical cam surface 41 of the mount with the tension springs 86 maintaining the cam edges resiliently in contact with the cam surface. As the slide member continues to be motivated along the rod in the direction of the mount, the arms are forced away from the longitudinal axis 42 of the mount so that the contact points 84 of the lateral extensions 83 are similarly directed outwardly. Assuming the cylindrical bore 36 is not already accurately centered, one or two of the contact points engage the cylindrical surface 35 as movement of the slide member is continued. During continuation of the movement, the contact points engaging the surface move the cylinder 30 in that direction until the contact points of all three arms engage the cylindrical surface. When this occurs the slide member is thereby restrained from further movement toward the mount and the operator is thus informed that the cylindrical bore 36 is positioned in precise axial alignment with the longitudinal axis of the mount and therefore the axis of rotation of the shaft.
The slide plates 21 of the boring machine 11 are then motivated toward each other to engage the cylinder 30 and are then locked in position so as to retain the cylindrical bore 36 in the precisely centered position. The centering tool is removed from the projection 18 either by directly pulling upwardly on the handle 52 or, particularly where the fit on the projection is snug, by grasping the slide member 60 and motivating it toward the handle until the striking end 62 of the member strikes the striking surface 53 of the handle. The resultant jolt is sufficient to release the mount 40 from the projection and allow the tool to be withdrawn from the cylinder. This method of removal also allows the contact points 84 to be retracted from the cylindrical surface 35 of the cylinder so as to avoid scoring during removal.
Therefore, the centering tool of the present invention is of a simplified and reliable construction not heretofore achieved in conventional centering tools thus maximizing the ease and speed with which the tool can be operated while minimizing the risk of error in the results produced.
Although the invention has been herein shown and described in what is conceived to be the most practical and preferred embodiment, it is recognized that departures may be made therefrom within the scope of the invention, which is not to be limited to the illustrative details disclosed.