Patent GB-560927-A (GB)
Title: Improvement in method of and mechanism for grinding
IPC: F02F1/20
Filed: 1941-08-11
Abstract: 560,927. Grinding. BRYANT CHUCKING GRINDER CO. Aug. 11, 1941, No. 10206. Convention date, Aug. 13, 1940. [Class 60] [Also in Group XXVI] A cylindrical or tubular work-piece, particularly the cylinder of an internal-combustion engine, is initially rough ground to true -cylindrical contour, and one or more portions are then finish-ground to a contour departing slightly from cylindrical. As applied to an internal-combustion-engine cylinder consisting of a barrel 55, Fig. 7, having threaded connection with a head, the finish-grinding operation is arranged to form. a slight enlargement 83 and construction 84 at the head-end, and a slight constriction 86 at the other end for the purpose of compensating for thermal expansion. A machine for performing the rough and finish grinding-operations comprises, as shown in Figs. 4 and 7, a grinding-wheel 7 carried by a swinging and laterally-movable head 3, the swinging movements being controlled by alternative abutments 20, 21 mounted on the head and co-operating with followers 31, 32 on feedscrews 35, 37 having automatic and manual operating-means. The abutment 21 consists of a straight rod and is employed during rough-grinding of the barrel. The abutment 20 is employed during finish-grinding and is formed with projecting parts 75, 74, a cylindrical part 70, and a reduced part 71 for controlling finish-grinding of the portions 84, 83, 85 and 86 of the barrel. Before finish-grinding, the grinding-wheel is trued by a tool 65 to a contour consisting of a central part 80 and reduced parts 81, the abutments 20 being formed with corresponding reduced parts 76, 77, 78 for controlling the grinding-wheel during trueing. In a modification, a single abutment 93, Fig. 9, and two trueing-tools 90, 91 are employed. Before rough-grinding the grinding- wheel is ground to cylindrical form by the tool 90, under control of a straight part a, c of the abutment. Rough grinding is performed under control of the part a, b. Before finish-grinding, the grinding-wheel is ground to convex form by the tool 91 under control of the part d, e. Finish-grinding is performed under control of the part a, b, the traverse being so limited that the grinding-tool does not clear the work, and the barrel being thereby formed with a cylindrical bore having reduced end-portions. The Specification as open to inspection under Sect. 91 describes also a tubular work-piece, shown in Fig. 16 (Cancelled), formed with a bore having slight tapers 101, 103 and sharp tapers 102, 104 in the following manner :- The tapers 103, 104 are formed by a grinding- wheel 106 which is formed with faces 109, 110 corresponding to the tapers and is provided with an extension-shaft 121 for attachment to the driving-shaft 108 on the swinging and laterally-movable head 3, an abutment 131 thereon being formed with parts fe, e, g for controlling the head during grinding of the tapers 103, 104. The abutment is formed also with parts hj, jk for controlling the head during trueing of the grinding-wheel. The tapers 101, 102 are formed by another grinding- wheel under control of another abutment carried by the head and formed with parts for controlling the head during grinding and trueing. The grinding-wheel has a short extension-shaft for attachment to the driving- shaft 108. This subject-matter does not appear in the Specification as accepted.