Patent GB-671575-A (GB)
Title: Rotatable hone
IPC: B24B33/08
Filed: 1950-02-27
Abstract: 671,575. Grinding cylinders. AMMCO TOOLS, Inc. Feb. 27, 1950 [March 3, 1949], No. 4972/50 Class 60. A rotatable hone for the internal grinding of cylinders comprises a body member 29, Figs. 2 and 5, having a plurality of circumferentiallyspaced slots 32 which are each intersected by a radius of the member along a line parallel with the sides 33, 34 of the slot and have a bottom wall 35 extending inwardly and forwardly with respect to the direction of rotation of the hone, abrasive carriers 36 mounted in, and shaped to correspond with, the slots, and separate means 62 mounted in each slot in operative engagement with the corresponding carrier for movement in opposite directions to expand and contract the latter. The body member 29 is in screw-threaded engagement at 28 with a tubular drive shank 26 which is provided with a driving head at its opposite end and on its exterior carries a slidable centering cone. Each carrier 36 is fitted with an abrasive stone 38 and maintained against axial displacement on the body 29 between plates 31, 41 on the latter, being urged to contracted position by a projecting -arm 51 on a spring 45 which is held between the plates 31, 41 in a longitudinal channel 48 in the body. Each of the members 62 is in the form of a slide provided with cam surfaces 66, 67 for engaging corresponding surfaces 68, 69 on the carrier 36 and is hooked at 65 to a cylinder 58 slidable in the enlarged bore 57 of the shank 26. A compression spring 60 disposed between the body 29 and the cylinder 58 urges the latter against a slidable push-rod 53 which at its outer end has a push-button for engagement manually or by the mechanism for driving the hone. In power operation, the machine controls are caused to effect rotation of the hone and axial movement of the push-rod 53 whereby the members 62 move inwardly to expand the carriers 36. In the modification shown in Figs. 9 and 10, the push-rod in the shank 26 is of telescopic form and comprises a rod 53 slidable within the shank within limits permitted by a pin 75 and slot 76, and a second rod 77 slidably within a bore in the rod 53 as permitted by a pin 79 and slot 80 and urged relatively to the rod 53 by a pre-loaded compression spring 81. The ends of the slides 62 are hooked on to a tubular member 82 which slides in the shank 26 and abuts the enlarged end of the rod 77. A compression spring 92, which requires less force to compress it than is needed to effect further compression of the spring 81, is located in the member 82 with one end abutting the head of a pin 90 projecting from the member 82 into engagement with the end of the body member 29. In operation, axial movement of the push-rod 53 acts through the spring 81 to move the rod 77 and thereby the member 82 axially, with compression of the spring 92, the slides 82 then causing expansion of the carriers 36 into honing contact with the work. Application of further pressure on the rod 53 merely causes the rod 77 to yield thereto with further compression of the spring 81. In this construction, the carriers 36 are urged to contracted position by springs 96 bent from single pieces of wire to form anchoring and engaging portions. The body member 113 shown in Fig. 17 has a universal connection 111, 112 with a head member 110, and the means for expanding the carriers 129 comprise a nut 117 which is urged by a spring 118 against the connection 112 and is screwed on to a slidable cage 120 having tongues 122 freely received in the slots 32 of the member 113. Each slide 121 has cam surfaces 125, 126 engaging cam surfaces 127, 128 on the corresponding carrier 129 and a projection 124 which hooks into a notch 123 in the cage 120. Rotation of the nut 117 in a direction to withdraw the cage 120 from the member 113 causes corresponding axial movement of the slides 121 and expansion of the abrasive stones 131 into contact with the work, the spring 118 being loaded so as automatically to expand the carriers as the work is abraded.