Patent GB-481907-A (GB)
Title: Improvements in hydraulic gears
IPC: F16H61/54
Filed: 1936-09-21
Abstract: 481,907. Hydraulic transmission of power. TENNANT, W. J. (Aktiebolaget Ljungstroms Angturbin) Sept. 21, 1936, No. 25655. [Class 69 (ii)] A hydraulic gear comprising, in a single liquid circuit, a pump ring, at least one rotating turbine ring and at least one non-rotating guide blade ring arranged after the turbine ring or, if there are two or more turbine rings, at least after the first turbine ring, is provided with an additional' non-rotating guide blade ring which can be introduced into, or withdrawn from, the circuit at a point between the pump outlet and the inlet of the turbine or the inlet of the first turbine, respectively, and which has blades so shaped as to reverse the direction of flow of the liquid after its discharge from the pump. The turbine blade ring may be exchangeable for a turbine blade ring provided with blades designed for backward running; alternatively, a blade ring forming an 'elongation of the turbine ring is arranged to be inserted into the working circuit, said blade ring being so shaped as substantially to reverse the direction of the outlet from the turbine ring.. The invention may be applied to a hydraulic gear having adjustable pump blades, the means for adjusting the pump blades and the means for adjusting the additional guide blades being combined with each other so as to be operable by a common actuating device ; the two adjusting means may be so combined that the guide blades are not moved into the liquid circuit until the pump blades have been closed, and vice versa. In a torque converter, Fig. 1, comprising pump blades 3, turbine blades 4 and guide blades 7, the additional guideblade member 12 can be moved axially into and out of the working circuit by a rod 13 ; the member 12 reverses the direction of flow of the liquid after it leaves the pump blades 3, and according to the extent to which it projects into the working circuit will control the forward speed of the turbine down to zero and then up to full reverse. As a further feature, Fig. 2, forward and reverse turbines 16, 17 are provided for selective operation the outlets of the turbine blades being oppositely directed to suit the conditions of flow of the working liquid in either direction. For moving the turbines axially, they are carried by a member 18 movable axially in a groove 19 in a projecting portion 20 of the turbine shell 21 and in threaded engagement with a ring 22 toothed at 23 to engage a gear wheel 24 journalled in the shell 21 and a disc 25 ; the wheel 24 engages a pinion 28 formed on the inner end of a sleeve 27 which can be rotated relative to the turbine shell, as, e.g. by planetary gear. Instead of providing forward and reverse turbines, auxiliary turbine blades 32, Fig. 3, may be provided for reversing the direction of the outlet from the turbine 31 at backward drive ; these additional turbine blades are moved into and out of the working circuit bv mechanism similar to that described with reference to Fig. 2. In a modification, Fig. 5, the torque converter comprises adjustable pump blades' 53, connected turbine blades 54, 55, guide blades 59 and auxiliary guide blades 85 arranged between the outlet from the pump blades 53 and the inlet to the turbine blades 54. The pump blades 53 are pivoted on pins 68 and are integral with rings 70 rigidly mounted in carrying members 71 formed into toothed segments 72 meshing with a common gear wheel 73 keyed on a sleeve 74 ; adjustment of the pump blades is effected by means of a lever 82 which moves a sleeve 77 axially ; the sleeve 77 has forks; some of these forks extend in the direction of the driving shaft 51 and engage radial pins 83 secured to the latter ; others of the forks are oblique to the direction of said shaft and engage pins (not shown) on the sleeve 74, whereby the latter, and therefore the pump blades, is rotated when the sleeve 77 is moved axially. The carriers 86 for the auxiliary guide blades 85 are splined at 92 to the stationary casing and are in threaded engagement with a ring 89 in toothed engagement with a pinion 90 on a shaft 91 projecting from the casing and operated in any suitable manner. In this form, control is normally effected by adjustment of the pump blades ; when, however, these are completely closed there is still some transmission of power due to leakage of liquid past the blades, and under these conditions, control is effected by introducing into the working circuit the auxiliary guide blades 85 the length of which is such that when they are completely in the circuit, the forward and reverse streams entering the turbine just equalize out and the turbine is not rotated. A modified form of torque converter, Fig. 9, comprises adjustable pump blades 103, turbine blades 104, stationary guide blades 107 and auxiliary guide blades 108 adapted to be inserted into the circuit. The pump blades 103 are pivoted on pins 102 and have carriers 109 formed as gear segments meshing with a gear wheel 110 formed on a sleeve 111 to which is keyed a ring 112 having inclined forks 113 engaging projections 117 on a sleeve 116 splined to the driving shaft 100 ; adjustment of the pump blades is effected by axial movement of the sleeve 116, this latter being effected, through the intermediary of a spring 99 by a sleeve' 121 axially movable by an operating lever 122 ; the sleeve 121 has an arm 124 which, when the sleeve 116 has been moved to such an extent that the pump blades are fully closed, acts on a flange 128 on a rod 125, 126 carrying the auxiliary guide blades 108 to move the latter into the circuit against the action of a spring 127 which normally holds them out of circuit. Forward and reverse turbines as described with reference to Fig. 2 or additional turbine blades as described with reference to Fig. 3 may be additionally provided in either of the forms described with reference to Figs. 5 and 9.