US2688219A

US2688219A - Grinding or honing tool with size control gauge means

Info

Publication number: US2688219A
Application number: US235738A
Authority: US
Inventors: Robert S Taylor
Original assignee: Individual
Current assignee: Individual
Priority date: 1951-07-09
Filing date: 1951-07-09
Publication date: 1954-09-07
Anticipated expiration: 1971-09-07

Description

Sept. 7, 1954 R. s. TAYLOR GRINDING OR HONING TOOL WITH SIZE CONTROL GAUGE MEANS Filed July 9, 1951 2 Sheets-Sheet l li vi INVENTOR.

Sept. 7, 1954 s, TAYLOR 2,688,21

GRINDING OR HONING TOOL WITH SIZE CONTROL GAUGE MEANS Filed July 9, 1951 2 Sheets-Sheet 2 4 Wg B8 v 11 7o 11: an? I90 I 70 IN V EN TOR.

Patented Sept. 7,1954

UNITED STATES PATENT OFFICE GRINDING OR HONDIG TOOL WITH SIZE CONTROL GAUGE MEANS Claims. 1

This invention relates to tools for grinding 'or honing surfaces and more particularly to means for controlling the movement of the abrading elements of such tools. This invention is related to that described and claimed in the copending application of the inventor entitled Grinding or Honing Tool and bearing Serial No. 209,223 and the filing date of February 3, 1951.

Heretofore in the honing or grinding of surfaces such as the walls of bores, it has been the practice to provide a rotatable body with one or more abrading elements and to employ some form of force applying means for effecting the expansion of the abrading elements relative to the body for engagement with the surface to be ground. Fluid pressure means has been suggested and employed for moving the abrading elements outwardly relative to the body. Considerable difiiculty has been encountered in the past in controlling the expandible movement of the abrading elements by fluid pressure or other force applying means and to stop or limit their expansion at the desired level of grinding.

An important object of this invention is to provide an improved grinding or honing tool having novel means for controlling the expansion of the abrading elements in an accurate and automatic manner. Another important object of the invention is to provide improved control means for tools of this character which is applicable to tools of various sizes and which enables the tools to be conveniently adapted and adjusted for various operating conditions. A further important object of this'invention is to provide a tool of this character having fluid pressure actuating means for the abrading elements which is arranged in the tool in a novel and eflicient man ner and further having fluid pressure control means for the abrading elements which is designed for use in larger tools of this character. In one form of the invention, a novel replaceable head or adaptor is provided on the tool with which is associated the measuring device for controlling the movement of the abrading elements.

Although the invention is herein illustrated as applied to grinding and honing tools, it is understood that the operating and controlling features thereof are applicable to other types of tools such as reaming and cutting devices.

Various other objects, advantages and meritorious features of the invention Will become more fully apparent from the following specification, appended claims and accompanying drawings herein:

Fig. 1 is a longitudinal sectional view of a honing tool embodying features of the invention,

V Fig. 2 is an enlarged cross-sectional view taken along line 2-2 of Fig. 1,

Fig. 3 is an enlarged cross-sectional view taken along line 3--3 of Fig. 1,

Fig. 4 is a longitudinal sectional view of a modified form of honing tool embodying features of the invention,

Fig. 5 is an enlarged cross-sectional view taken along line 5--5 of Fig. 4, and

Fig. 6 is an enlarged cross-sectional view taken along line 66 of Fig. 4. With reference to the drawings, the grinding or honing tools illustrated therein are adapted to be attached to a part of a machine which is rotatable and axially movable while rotated. During its rotation, the abrading elements of the tools are constructed and arranged to be expanded radially outwardly therefrom for grinding a surface such as the wall of a bore of a workpiece into which the tool extends.

With reference to the embodiment of the invention illustrated in Figs. 1, 2 and 3, the tool in general comprises a lower body portion l0 and an upper body portion l2 which is attached to the machine part. The body [0 carries one or more abrading elements I4 referred to as honing sticksor stones, there being eight of such elements shown in the two embodiments of the invention illustrated herein. The abrading elements or stones are arranged in equally circularly spaced apart relation around the axis. of the head II] and are capable of radial expansion therefrom as hereinafter described. The body ID of Figs. 1 to 3 is preferably substantially exteriorly cylindrically shaped and of a diameter slightly less than that of the bore size for which it is intended in order to freely enter the bore. The head H] is interiorly shaped with a longitudinal passage or bore US which as shown in Fig. 1 may open out through the opposite ends of the head. Cut or otherwise formed in the body It! are a. plurality of longitudinally extending slots or grooves i8 which correspond in number to the number of honing stones carried by the head and open into the passage It. The slots are shaped to receive the stones therein in slight projecting relation to the exterior surface of the head. Each honing stone [4 is capable of radial movement in its respective slot or groove as will be explained more fully hereinafter.

Also carried by the body portion II] of the tool are one or more measuring implements in the form of sizing elements or pins 20 which are positioned on the body so as to contact the surface engaged by the honing stones. In the illustrated embodiment of the invention, four such sizing elements or pins are shown and they are arranged in equally circularly spaced apart relationship to one another and angularly off-set to the grooves l8 so as to be disposed between certain pairs of the grooves. The sizing pins may be of the cylindrical formation shown and disposed in a transverse plane preferably midway between the opposite ends of the honing sticks [4, such as on the section line 22 of Fig. l. The outer ends of the pins may be rounded as shown and may be provided with carboloy or diamond inserts for contact with the surface to be ground.

Reciprocably mounted in the bore or chamber I6 of the body 10 is an actuator for the abrading elements or stones I4. The actuator is generally indicated at 22 and is also herein referred to as a cone member since it is provided with at least one conical shaped surface. In the illustrated embodiment of the invention, the actuator 22 is provided with two axially spaced apart conical sections 24 and 26 which are connected together into a unitary assembly and may be shaped out of one piece.

Although the support for each honing stick or stone I4 may be of any suitable type for the purpose intended, it is herein shown as being composed of a shallow channel shaped member 28 into which the inner end of the stone is received as shown in Fig. 2. The channel member 28 extends the length of the stone and is provided at the opposite ends with two similarly formed projecting flanges or lips 30-30 as shown in Fig. 1. To the bottom side of each channel member 2 8 there is secured a hone guiding member 32 Which is capable of radial movement in the slot l8 of the head in which the stone is mounted. Between each guiding member and actuator 22 there is provided a plate member 34 having a straight outer edge which abuts the bone guiding member and a notched inner edge shaped to engage the conical surfaces of the actuator. As shown in Fig. 1, each plate member is provided with two longitudinally spaced apart inclined surfaces 36 and 38 having the same inclination as the conical surfaces of the two sections 24 and 26 of the actuator for facial contact therewith. It is evident from the assembly thus far described that upon longitudinal movement of the actuator in one direction, such as the downward direction in Fig. 1, it will act through the cam or inclined surfaces of the plate members 34 to simultaneously force the abrading stones [4 outwardly of the body.

The upper end of the body portion l0 may be reduced in lateral extent as shown at 40 and secured to the bottom end of the upper body portion l2 of the tool for joint rotation therewith. The latter is provided with an axial passage 42 therethrough. Into the lower end of the passage there is fitted a tube 44. The tube projects .beyond the lower end of the body portion [2 of the tool and into the chamber or bore 16 of the body portion l0 and terminates adjacent to the cone member 22. As hereinafter described, fluid under pressure is directed through the passage 42 and the tube 44 and is utilized to force the cone member downwardly to expand the honing stones. To assist in such movement, there is provided a piston or plunger 46 in the lower end of the tube 44 which slidingly fits the tube and abuts the upper end of the cone member. The plunger may be provided with a peripheral groove 48 into which sealing material may be placed to prevent escape of fluid beyond the lower end of the tube. Fluid pressure in the tube 44 acts upon the upper end of the plunger forcing the latter downwardly and causing the cone member to move below the position shown in Fig. l to expand the honing stones.

The upper end of the tube 44 terminates within the passage 42 of the upper section l2 of the tool and preferably on a level approximately midway between the opposite ends of the passage as shown in Fig. 1. At this point, the tool is provided with a valve for controlling the amount of fluid entering the tube 44 and acting on the cone member 22. This valve is herein shown as a ball 50 of such a dimension as to seat on the upper end of the tube 44 and cut off the delivery of fluid therethrough. The ball Valve is yieldingly urged to closed position by means of a coil spring 52. One end of the spring seats on the ball valve and the other end abuts a fitting 54 threaded in the upper end of the passage 42.

The fluid pressure acting through the piston 45 and the cone member 22 to expand the abrading elements [4 is yieldingly opposed by spring means. This may comprise a pair of coiled type garter springs 5656 encircling the body l0 and overlying the projecting lips 30 of the channel members 28, one at each end thereof. These garter springs are tensioned to exert a force sufficient to contract the abrading elements to their minimum projecting condition when the fluid pressure is relieved. These springs hold the inclined faces 36 and 38 of the plate members 34 in continuous contact with the conical surfaces of the actuator 22.

The upper end of the body portion 12 is interiorly widened to form a cavity 58 into which the passage 42 opens. Into this cavity there is received the lower end of a shaft-like connector 60 which is detachably secured to a rotating part of the machine. The connector and the upper body portion I2 are drivingly coupled together in the cavity 58 by means which they permit the two body portions [2 and [0 to assume a slight angular relation to the axis of rotation of the connector. For this purpose, the inserted end of the connector is provided with a plurality of circularly spaced apart radially projecting pins 62 which enter aligned holes in the wall of the cavity 58.

The connector 60 is axially bored out to provide a relatively wide longitudinal passage 64 which opens out through the lower end thereof and in alignment with the passage 42 in the body portion [2 and the fitting 54. The upper end of the passage 64 communicates with an axial passage 65 of reduced cross section in which a fitting 38 similar to fitting 54 is threadedly engaged. The passage 68 communicates with a source of fluid pressure such as a cylinder 10 in which a piston (not shown) is reciprocable. The passage 66, however, may communicate with an outside source of fiuid pressure associated with the machine and delivered by conduits to the upper end of the connector 60.

The two

fittings

54 and 68 are axially bored completely therethrough as shown in Fig. 1. Each fitting 54 and 68 is fianged for abutment against the adjacent end wall of the bore 64 and further provided with a tubular portion, such as indicated at 12 and 14 respectively, which project into the passage 64 of the connector. Extending between the tubular portions of the two fittings and being sealingly connected thereto is a tubular member 16 of resilient material.

The I assspis hollow interior of the tubular member forms a duct 18 establishing communication between the passage 66 of the connector and the passage 42 of the upper body portion [2. Preferably, the tube It is relatively stiff yet sufficiently flexible to provide a tight connection with the tubular portions of the

fittings

54 and 68 when any slight out-of-alignment relation occurs between the connector 69 and the tool section l2. The outer diameter of the tubular member is less than the lateral dimension of the passage 64 through which it extends and its flexible character enables it to follow any angular displacement of the working end of the tool relative to the connector 60 while maintaining a sealed conduit for the flow of fluid therebetween.

The measuring elements or sizing pins 20 automatically control the extent of the abrading stones l4 project from the body It) and thereby regulate the level to which the abrading stones grind the surface engaged thereby. This is accomplished by operatively connecting the valve 50 with the sizing pins and controlling the action of the valve by the position of the pins. As herein shown the operative connection is formed by a confined body of fluid separate from the fluid employed to shift the honing stone actuator 22.

Drilled or otherwise formed in the body II] are passages which communicate with one another and the bases of the sizing pins 20. Three such passages are shown at 80, '32 and 84 and they may be located near the upper end of the body and in the plane of the cross section on which Fig. 3 is taken. Each passage may be formed by drilling from the outside of the body [0 in a straight path off set to the bore l6 and between the latter and the exterior of the body It). The three passages intersect one another in the manner shown in Fig. 3 to provide communication therebetween. The outer ends of these passages are sealed by plugs 86. Extending from the connected

passages

80, 82 and 84 and leading to each sizing pin 20 is a separate longitudinal passage, one of which is shown at 83 in Fig. l. The longitudinal passages are circularly spaced around the axis of the body If) in radially offset relation to the bore 56 thereof and communicate at their lower ends with short radial passages 96 in which the sizing pins are guided for movement. As shown in Fig. 1 the longitudinal passages 85 extend through the thick portion of the body it between its exterior surface and the Wall surface of the bore [6.

Communicating with the intersecting

passages

80, 82 and as and extending upwardly therefrom is a tube as. The tube 92 is connected to the shoulder 94 formed on the body [0 by the reduced end section ill thereof and extends to the upper body i2. Fittings 94 and 9t connect the upper and lower ends of the tube to the body portions 12 and ii] respectively and serve to support the tube in lateral off-set relation to the reduced end section till. An inwardly directed passage 98 in the body portion i2 opens into the conduit A l at a point slightly below the ball valve 50. Reciprocably movable in this inclined passage is a pin or phinger iii the inner end of which is tapered or rounded for abutment with the spherical surface of the'ball valve. The plunger I00 is provided with one or more peripheral grooves H32 in which sealing material is placed to prevent leakage of fluid passed the plunger. It is evident that upon inward movement of the plunger I00 it willengage and raise the ball valve 6, above its seat opening communication between the passage 42 and the conduit 44 leading to the actuator 22.

During the operation of the tool fluid under pressure is contained within the intersecting passages 80, '82 and 84, longitudinal passages 88, tube 92 and the outer end of the inclined passage 98. The fluid pressure acts through the plunger [00 to unseat the ball valve. The pres sure of the fluid in these various interconnecting passages is controlled by means which is accessibly positioned on the outside of the tool. As shown in Fig. 1, one of the longitudinal passages 88 is provided with a downward extension [04 which opens into a radial passage Hi6 extending to the exterior of the body [8. Located in the passage I06 is a threaded member or cap me which may have a screw driver receiving slot on the outer end thereof. It is evident that with the sizing pins held immovable any rotation of the cap in the direction to move it inwardly will increase the pressure of the fluid contained within the interconnecting passages. This increased pressure will cause the plunger IGG to unseat the ball valve 56. It is obvious that upon rotation of the cap in the opposite direction it will reduce the pressure and permit the ball valve to seat.

It is preferred to use incompressible fluids for moving the actuator 22 and for controlling the ball valve 50. Suitable fluids for-this purpose are either light or heavy oils such as used for lubrieating or hydraulic purposes. It is understood that the two fluid bodies are kept separate from one another, and that one controls the action of the other as hereinafter described.

In the operation of the device, the fluid in the interconnecting passages which acts on the sizing pins is initially adjusted to the desired amount to shift these pins to the prescribed diameter of the bore or surface to be ground. This may be accomplished, for example, by inserting the body it of the tool into a bore of a gauge having the precise diameter to which it is desired to grind the bore of a work piece. While in the gauge, the cap 108 is threadedly adjusted to build up pressure on the confined fluid sufficient to project the sizing pins outwardly into engagement with the wall of the gauge bore without, at the same time, unseating the ball valve 59. There after, the body ii] of the tool is inserted into the bore of a work piece to be ground. Since this bore is of less diameter than that for which the sizing pins have been set, the latter will be compressed or forced radially inwardly by the engagement with the bore. Since the confined liquid associated with the sizing pins is incompressible, the only element which is movable to allow the sizing pins to collapse is the plunger I00. This will move upwardly and inwardly under the pressure developed and unseat the ball valve and open the tube it to the flow of fluid pressure from the connecter The fluid pressure developed in the tube 44 by the unseating of the valve will cause the plunger t6 and the actuator 22 to move downwardly and force the honing stones radially outwardly and into engagement with the bore to be ground.

As the bore of the work piece is ground by the engagement of the honing stones therewith, the pressure of the fluid within the interconnecting passages leading to the sizing pins 253 causes the latter to move outwardly with the honing stones and maintain continuous contact with the wall of the bore. As the sizing pins move outwardly in their respective passages during the grinding or honing operation, they permit the fluid confined in the interconnecting passages leading to the plunger I to follow their movement and thereby reduce the pressure acting on the plunger. When the sizing pins reach the diameter for which they are initially set, the plunger I00 will have travelled outwardly and downwardly in passage 98 sufiicient to bring the ball valve into seated position where it will cut off further delivery of fluid through the tube 44 to the actuator. This will automatically prevent further outward radial movement of the honing stones and discontinue the grinding operation even though the tool continues to rotate. If the bore to be ground is deep and the tool is axially moved into an unground section, the sizing pins as will be slightly collapsed by the smaller diameter of the bore causing the valve to be unseated, and in this manner the operation of grinding the bore may be continued without the necessity of any adjustment of the tool from a ground section to an unground section of the bore.

The modification of the invention illustrated in Figs. 4, and 6 is generally similar to the embodiment previously described but diners primarily in the provision of a detachable head or adaptor containing the sizing pins and the location of the control valve in the connecting shaft of the tool rather than the tool proper. Referring to these figures the tool body is generally indicated at I I0 and comprises a one piece member divided longitudinally into two sections H2 and H4. The lower section H2 carries the abrading elements or honing stones i It in circularly spaced relation therearound. These stones are guided for radial outward movement in two axially spaced apart circular flanges I I3 and 520 which project outwardly from the body portion II2. Radial slots I22 are provided for mounting and guiding the honing stones as shown in Fig. 5. Each stone is supported upon a channel shaped member I24 similar to member 28 previously described and these members are constructed to receive garter springs I2EI2I5 which yieldingly draw the members and their respective stones into contracted position against the body portion H2. Each channel member is supported upon and secured to a hone guiding member I28 siniilar to the members 32 of the previously described embodiment of the invention.

The body portion I I 2 is hollowed out interiorly to provide a bore or passage I30 which as shown in Fig. 4 opens out through the lower end of the tool. Reciprocally mounted in the passage I38 is an actuator I32 shaped similar to the actuator 22 and provided with two axially spaced apart conical sections I34, and I39. In lieu of plates 34, pins I38 are provided for operatively coupling the actuator with the honing stone guide members I28.

The upper body portion H4 is widened and provided with an end opening cavity I43 into which the lower end of a connecting shaft M2 extends. The shaft I42 is axially bored out to provide a passage I44 which opens out through the inserted end of the shaft. The upper end of the chamber I30 is provided with an end wall I46 having an aperture therethrough in axial alignment with the passage I44 and of the same diameter. Reciprocal in the passage I 50 is a piston or plunger I48 which is similar in function to the plunger 46 of the previously described embodiment of the invention and abuts the upper end of the actuator I32 in the manner shown in' Fig. 4.

Th inserted end of the shaft or connector I42 is provided with a spherical ball-shaped end section I50 which constitutes a part of a universal joint. Carried by the spherical end section are one or more locking balls I52 which drivingiy couple the connector to the body III]. For this purpose the inner Wall of the cavity I is provided with grooves I54 in which the balls I52 are partly received. In this manner the connector I42 is drivingly coupled to the body III! for joint rotation yet permitting the ball to have a limited universal movement relative to the connector to accommodate itself to any misalignment of the tool in the bore to be ground.

The upper end of the cavity I40 is closed by an externally threaded sleeve I56 which is threaded to the upper end of the cavity. The inner or minimum diameter of the sleeve I56 is slightly greater than th external diameter of the connector I42 to provide a slight clearance therebetween for permitting a limited angular movement of the connector relative to the tool body IIG. Between the sleeve I56 and the universal ball joint I there is provided a retainer member I58 having a beveled edge I50 bearing upon the universal ball joint in the manner shown in Fig. l. The retainer is lightly pressed into engagement with the ball joint by the threaded engagement of the sleeve I56 with the wall of the cavity. The retainer is likewise provided with an internal diameter slightly greater than th inserted end of the connector in order to provide the limited angular movement between the connector and the tool body. The sleeve I56 is locked in place by a ring I 82 threaded thereto and abutting the upper end of the wall of the cavity I40.

The connector I42 is provided with a control valve similar to the valve 50 of the previously described embodiment of the invention. As shown in Fig. 4, the passage I44 of the connector is widened above the plunger I48 to receive a sleeve Hit. The lower end of the sleeve I64 is shaped to provide a valve seat for receiving a ball valve member I66 which functions like the ball valve '50 previously described. The ball valve is yieldingly urged to valve closing position by mean of a coiled spring I68 inside of the sleeve in the manner shown in Fig. 4.

The valve I56 is controlled by a separate fluid pressure operating means associated with measuring elements or sizing pins carried by the tool.

. In the embodiment of the invention illustrated in Figs. 4, 5 and 6, the sizing pins, indicated at I'iil, are carried in a separate member of the tool forming an adaptor or head attached to the lower or leading end of the tool. The head is referred to by reference character I12 and as shown in Fig. 4 is circularl formed so as to have a diameter proximating that of the flanges H8 and I20. The head is removably attached to the lower end of the body I I 0 by means of screws I14. Its removable character enables the head I12 to be replaced by other similar heads having sizing pins of different constructions and dimensions to accommodate the tool to different working conditions.

The sizing pin adaptor or head I12 is provided internally with a plurality of interconnecting passages for delivering fiuid under pressure to the bases of the sizing pins. As shown in Fig, 6 the adaptor is drilled to provide a set of interconnecting passages I16, I18 and I similar to the

passages

80, 82 and 84 of the earlier described embodiment. The outer endsof these passages are sealed by plugs I82. The sizing pins IIIl are each slidably guided in radial passages Hi l which open into the interconnecting passages I16, I18 and we in the manner shown in Fig. 6.

Providing an operative connection between the adaptor or head I12 and the valve Itli is a narrow tube I86 which as shown in Fig. 4 extends for more than the length of the body III! and in radially offset relation to the bore Itll in which the actuator I32 reciprocates. The tube I86 may extend through the flanges H8 and 12s for support thereby and may extend upwardly past the universal ba11 joint connection in slight radial spaced relation thereto. The narrow tube I 85 has a degree of flexibility which allows it to bend to follow any angular displacement of the connector relative to the tool body I Hi.

The tube I86 is connected at its lower end by a fitting I88 to the head I72. The fitting opens into communication with the interconnecting passages I75, I18 and IE9. The upper end of the tube I86 communicates with an inwardly and upwardl inclined passage I90 in the connector I42 which opens into the passage its at a point slightly below the ball valve Hit. The form of connection between the tube I86 and the connector may be of any suitable character such as the two pipe connecting fittings I92 and I94 shown in Fig. l. Reciprocal in the inclined passage I90 is a plunger I96 similar in function to the plunger IDEI previously described. This plunger abuts the ball valve and upon increase in pressure of the fluid within the tube I86 will move inwardly to unseat the valve and provide communication be tween the sleeve IM- and the passage i l of the connector. The fluid pressure within the interconnecting passages I'IS, I18 and I 38 and the tube I85 is controlled by a threaded member or cap I93 located in the head. The cap is received in a passage 2% which is in communication with the interconnecting passages and like the cap H18 previously described its threaded adjustment will vary the pressure of the fluid confined in these passages and the tube I86 to vary the projecting portion of the sizing pins ITIII.

The operating movement of the actuator I32 may be yieldingly opposed by means associated with the adaptor or head I72 and capable of being interchanged at the time the head is removed.

As shown in Fig. 4, a coiled spring 292 is provided in the lower end of the bore I3!) which is seated at its upper end on a plate or disc 204 secured to the lower end of the actuator I32. The opposite end of the spring enters acentral aperture 2% in the head ill and is seated upon a plate or disc 20$ carried by the head H2. This disc is removable from the head and for such purpose it may be threadedly engaged in the aperture 2% as shown in Fig. 4.

The operation of the modification shown in Figs. 4, 5 and -6 is similar to the operation of the previously described embodiment of the invention. A selected head or adaptor I72 is secured to the lower end of the body HI! and the fitting I88 is threaded into the opening in the head intended therefor. The tool. is then inserted into a gauge .bore and the cap I88 adjusted sufiiciently to bring the sizing pins into engagement with the wall of the gauge bore. Thereafter, the tool is inserted in the bore to be ground and operates in a similar manner as the earlier described embodiment of the invention to control and limit the outward expansion of the abrading members H6.

The invention is applicable to honing and grinding tools of various types and sizes. As typified by the two embodiments of the invention illustrated herein, the toolsare designed so that the abrading elements or stones are thrust outwardly by mechanical force applying means located internally of the tool body, such as the actuators 22 and I32. This enables fluid pressure to be delivered axially of the tool body for moving the actuator where it is sealingly confined within the tool against leakage. The fluid pres sure conducting mean between the sizing pins and the valves are located in radially offset relation to the actuator and their respective bores in which they operate in order to permit the utilization of centrally located mechanical actuating means for the abrading elements.

In the embodiment of the invention illustrated in Figs. 4, 5 and 6, the adaptor or head containing the sizing pins is shown located on the lower or leading end of the tool body but it is understood that such a detachable unit might be mounted at any other suitable place on the tool such as above or in trailing relation to the honing stones. In this embodiment the control valve I 66 is located at a relative remote distance from the honing stones and in the fluid delivery conduit leading to the tool body. The valve, however, might be located in the tool body as shown in the embodiment illustrated in Figs. 1, 2 and 3.

What I claim is:

1. In a grinding or honing tool, a rotatable body having a central longitudinally extending bore therein, a plurality of radially movable abrading members carried by the body in circularly spaced relation around the bore and capable of being moved radially outwardly of the body for engagement with a surface to be ground, a plurality of radially movable sizing elements carried by the body in circularly spaced relation around the bore therein and between said abrading members and capable of being moved radially outwardly of the body for contact with the same surface en gaged by the abrading members, means for delivering fluid under pressure into one end of the bore, a valve in said fluid delivery means, means in said bore responsive to the fluid pressure thus delivered for moving the abrading member radially outwardly of the body, conduit means ex-, tending longitudinally of the body in olT-set relation to the bore therein and communicating at one end with said sizing elements and at the other end with said fluid pressure delivery means, a valve control member slidably but sealingly fitting the last mentioned end of the conduit means and operably connected to the valve for control.- ling the same, said conduit means containing a body of incompressible fluid which operatively connects the sizing elements with the valve control member and renders the latter responsive to the outward movement of the elements.

2. In a grinding or honing tool, a rotatable body having a central longitudinally extending chamber therein, a plurality of radially movable abrading members carried by the body in circularly spaced relation around the chamber and capable of being moved radially outwardly of the body for engagement with the wall of a bore into which the body is inserted, a cone member reciprocably movable in the chamber of the body and operatively connected to the abrading members such that upon movement in one direction it forces the abrading members outwardly of the body, a fluid conduit entering one end of the body,

, spring means urging the valve to closed position,

a valve in said conduit, a piston in said conduit operatively connected to the cone member and responsive to the fluid pressure in the conduit to move the cone member in said direction to force the abrading members outwardly of the body, said body having a plurality of outwardly opening recesses arranged in circularly spaced relation around the chamber but terminating short thereof, a projectionable sizing element in each r cess, means for exerting a force on the sizing elements to urge the same outwardly of the body in order to maintain continuous contact with the wall of the bore being ground by the abrading members, said last means including a second conduit extending longitudinally of the body in radially oil'- set relation to the chamber therein and opening at one end into the basis of said recesses and at the other end into said first conduit, said second conduit containing an incompressible flowable medium, and a plunger in said other end of the second conduit serving to seal the same against the escape of said medium and to engage and hold the valve in open position, said medium adapted to flow toward said recesses in response to outward movement of the sizing elements and thereby causing said plunger to move in the direction to permit the valve to move to closed position.

3. In a grinding tool, a rotatable body carrying a plurality of abrading members circularly spaced therearound and mounted for movement radially outwardly of the body, fluid pressure responsive means in the body for moving the abrading members outwardly from the body, means entering one end of the body for delivering fluid under pressure to said fluid pressure responsive means, a valve in said fluid delivery means, a head detachably secured to the opposite end of the body and carrying one or more measuring elements mounted for movement radially outwardly of the head for measuring changes in the surface engaged by the abrading members, fluid pressure means in said head for moving the one or more measuring elements outwardly from the head, a conduit extending longitudinally of the body and communicating at one end with the fluid pressure means in the head and terminating at the opposite end adjacent to said valve, and means in the latter end of the conduit operatively connected to said valve and responsive to the change in the fluid pressure of the conduit for controlling the valve.

4. In a grinding tool, a rotatable body, an abrading member mounted in the body for movement outwardly relative to the body, actuating means in the body responsive to fluid pressure for moving the abrading member outwardly from the body and into engagement with a surface to be ground, means connected to one end of the body and opening axially thereinto for delivering fluid under pressure for operating said actuating means, a valve associated with said fluid delivery means for controlling the flow of fluid therethrough, a second body associated with the tool, a measuring element mounted in the second body for movement outwardly therefrom, means in said second body for applying fluid pressure for moving the measuring element outwardly and into engagement with the surface to be honed by the abrading member, means detachably connecting the second body to the first body, a conduit detachably connected to the second body and extending longitudinally of the first body in radially offset relation to the abrading actuating means therein and terminating adjacent to said valve, an incompressible fluid in the conduit, and means in said terminating end of the conduit having an operating connection with the valve and responsive to flow of the incompressible fluid in the conduit for controlling the position of the valve.

5. In a grinding or honing tool, a rotatable body having a central longitudinally extending bore therein, a plurality of radially movable abrading members carried by the body in circularly spaced relation around the bore and capable of being moved radially outwardly of the body for engagement with a surface to be ground, a fluid operated cone shaped member reciprocably mounted in said bore and operable upon movement in one direction to move the abrading members radially outwardly, means for moving said cone member in said direction including a fluid pressure delivery conduit opening axially into one end of the bore, a valve in said fluid delivery conduit, said body provided with at least one substantially radially opening passage, a sizing element in each such passage and movable outwardly into engagement with the wall of the bore into which the tool is inserted, means for activating the valve from each sizing element including a second conduit extending longitudinally of the body in radially off-set relation to the bore therein and opening at one end into each sizing element passage and provided at the other end with an inturned section which opens into said fluid delivery conduit at a point adjacent to said valve, and a substantially incompressible mobile medium in said second conduit operatively coupling the valve to each sizing element such that when the latter moves outwardly the valve moves toward the position to close the fluid delivery conduit.

6. In a grinding or honing tool, a rotatable body having a central longitudinally extending bore therein opening out through the opposite ends of the body, a plurality of radially movable abrading elements carried by the body in circularly spaced relation around the bore and capable of being moved radially outwardly of the body for engagement with a surface to be ground, a fluid pressure delivery conduit entering one of said ends of the bore, a valve in said conduit operable to open or close the same, spring means urging the valve toward valve closed position, a member reciprocably movable in said bore and operatively coupled to the abrading elements for moving the same outwardly when the member moves in one direction of its movement and for permitting the abrading elements to move inwardly when the member moves in the opposite direction, said member being responsive to the fluid pressure admitted into said bore by the conduit, said body provided with at least one outwardly opening passage located closer to the opposite end of the body than the valve, a sizing element in each of said passages and movable outwardly to engage the surface to be ground, means forming an operative connection between each sizing element and the valve and rendering the valve responsive to the movement of each sizing element such that when the element moves outwardly the valve is permitted to advance toward closed position, said means extending in radially oif-set relation to the bore of said body, and a second spring means positioned in the opposite end of the bore to that entered by said conduit and operatively connected to said reciprocable member in the bore so as to yieldingly oppose the movement thereof in the direction to move the abrading elements outwardly of the body.

7. The invention described in claim 6 characterized by the provision of means for adjusting 13 the tension of said second spring means to vary the spring pressure exerted thereby on the reciprocable member in the bore of the body.

8. In a grinding or honing tool, a rotatable body having a central axially extending bore therein, a plurality of radially movable abrading elements carried by the body in circular spaced apart relation around the bore, a member reciprocably movable in the bore and so operatively connected to the abrading elements that when moved in one direction it forces the abrading elements outwardly of the body and when moved in the opposite direction it permits the elements to retract radially inwardly, a fluid pressure delivery conduit opening into one end of the bore and operable to deliver fluid under pressure thereinto to move the member in the direction to force the abrading elements outwardly of the body, a valve in said conduit cooperating with a valve seat and movable into engagement with the valve seat to close the conduit and movable away from the seat to open the conduit, spring means urging the valve toward valve seat engaging position, said body having at least one outwardly opening passage therein located closer to the opposite end of the body than the valve, a sizing element in each of said passages and movable outwardly thereof to engage the surface to be ground, means forming a remote operating connection between each sizing element and the valve including a conduit having a part thereof extending longitudinally of the body in radially off-set relation to the bore thereof and communicating at one end with each sizing element passage and at the other end with the first conduit between the valve and the bore, a substantially incompressible mobile medium in said second conduit, and a valve unseating plunger entering said other end of the second conduit and being responsive to the movement of the mobile medium to either unseat the valve or permit the same to engage the valve seat.

9. In a honing device of the type in which an abrasive element is applied against and moved laterally of a surface to be honed, means mounting the abrasive element in the body and providing for movement thereof toward and away from the surface to be honed, means in the body for shifting the abrasive element relative to the body and into engagement with the surface to be honed, control means carried by the body for controlling the action ofsaid abrasive element shifting means and operable to either permit or prevent the action of the shifting means, a

second body, a measuring element, means mounting the measuring element in the second body and providing for movement thereof toward and away from the surface to be honed, means detachably connecting the second body to the first body, an elongated force transmitting medium carried by the first body and terminating at one end adjacent to said control means and at the other end adjacent to the second body, means operatively coupling the first mentioned end of the force transmitting medium to the control means, means detachable connecting the second mentioned end of the force transmitting medium to the second body, and means operatively coupling the detachable end of the force transmitting medium with the measuring element and rendering the medium and the control means responsive to its movement.

10. In a grinding tool, a rotatable body carrying a radially expandible and contactible abrading element, means in the body for expanding said abrading element into engagement with a surface adjacent to which the body is disposed, control means for governing the action of said expanding means and operable to permit or prevent the operation thereof, a separate head, a measuring element carried by the head and being urged outwardly therefrom for contact with the surface engaged by the abrading element, means de'tachably connecting the head to the body to provide replacement of the head and associated measuring element, an elongated force transmitting medium extending between the body and the head, one end of the elongated medium being operatively connected to the control means and the opposite end being operatively connected to the measuring element and rendering the control means responsive to the movement of the measuring element, and means for disconnecting the force transmitting medium from the head.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 2,252,809 Kline Aug. 19, 1941 2,284,325 Kline May 26, 1942 2,318,830 Crompton May 11, 1943 FOREIGN PATENTS Number Country Date 509,718 Great Britain July 20, 1939 OTHER REFERENCES American Machinist, May 22, 1947, page 162.