Patent GB-590337-A (GB)
Title: Improvements in apparatus for transporting articles from one station to another
IPC: F41A9/51
Filed: 1944-09-06
Abstract: 590,337. Screw conveyers. NICHOLLS, K. H., TINDALE, J., GILBERT, J. A., and ROSE BROS. (GAINSBOROUGH), Ltd. Sept. 6, 1944; No. 17078. [Class 78(i)] [Also in Group XXI] In conveyers for transporting articles from one station to another, e.g., for transporting rounds of ammunition to the loading station of a quick-firing gun, timing means is provided in association with means for starting and stopping the driving mechanism of the conveyer for r automatically stopping the conveyer in a predetermined article-receiving position, the timing means also being connected to the means for feeding articles to the conveyer to ensure that the feeding mechanism can operate only when the conveyer is stopped in the correct position. Each charger, which contains f o u r rounds, is placed on a pivoted feeding tray 51, Fig. 2, for delivery to a screw conveyer 12 in a casing 11 which carries it to the gun loading station 14. The axis of the conveyer is not vertical as shown in the figure, but is inclined thereto. The conveyer shaft 16 is coupled to the rotor 17 of an oil motor 18 to which oil is supplied by a pump driven by an electric motor 21. Downward extensions 56 of the tray are connected by a pair of links 57 to a pivoted arm 58 carrying a roller 59 which bears against a cam 61 on the shaft 16. One of the links 57 is pivoted to an arm 62, Fig. 3, on a shaft 63 which carries a helical cam 64 at its lower end. An annular member 67, Fig. 1, disposed about the axis of the conveyer is pivoted in a pair of brackets 66 depending from the casing 11 and is provided with a member 68 which is maintained in engagement with the cam 64 by a spring 69. A two-armed lever 25, 26 is pivoted in an axial shank 22 formed on the sleeve valve of the motor 18 and carries a roller 27 which runs on an annular cam track 28 secured to the stator of the motor. The arm 25 is connected by a link 31 to a lever 32 which is pivotally mounted on the shaft 16 for movement about an axis parallel to the pivotal axis of the lever 25, 26. A roller 33 mounted on the free end of the lever 32 engages the annular member 67 during that part of the rotation of the screw 12 in which the member 67 is tilted by the cam 64. The parts are so arranged that when the roller 33 is at the peak of the member 67, the disposition of the lever 32 is the same as when it is raised by the action of a feeler 39 at the gun-loading station. In this position the valve is in neutral position, the motor is at rest and the tray 51 is in its normal feeding position, i.e. in a plane normal to the conveyer axis. The links 57 are connected by a crossbar 88, Fig. 3, which is attached to a casing 87. This casing contains a compression spring 86, Fig. 2, and a pair of collars 84 which are freely mounted on a reduced portion 83 of a slide bar 82. A slot 81 in this bar receives the eccentric portion 79 of a shaft 76 which is mounted on the casing 11 and manipulated by a crank handle '78. Spring catches 89 hold the handle 78 in each of its two operative positions. In one position the eccentric 79 compresses the spring 86 towards the tray 51 to an extent sufficient to cause the links 57 to turn the tray to normal position and at the same time force the roller 59 into contact with the cam 61. In the other position, which is at 180 degrees to the first one, the spring is compressed in the opposite direction with the result that the roller is removed from the cam and the tray is tilted to cover the aperture in the casing. When the handle is in the first position, the cam 64 is in such a position that the member 67 is pivoted to the maximum extent and the valve-operating cam 29 is engaged by the roller 27, the valve is in neutral position and the conveyer is stationary. In operation a charger is placed on the tray 51 and allowed to slide into the conveyer. The tray is then tilted by depressing the handle 91 and is then released to be returned to charging position by the spring 86. This momentary tilting removes the roller 59 from the cam 61 and also rotates the cam 64 thus permitting the member 67 to turn away from its position of maximum inclination. Since this movement withdraws the support from the roller 33, the lever 32, together with the twoarmed lever 25,26, is pulled downwards by the valve spring and at the same time the roller 27 is lifted clear of the cam 29. In consequence the valve is moved to start the motor and the screw 12 starts to rotate. After a very slight rotation of the cam 61, its operative part moves clear of the roller 59. Consequently when the tray is released to move downwards, the roller 59 returns to the concentric surface of the cam. When the screw has nearly completed one revolution, the operative portion 71 of the cam 61 again bears against the roller 59 and permits the arm 58 to rock under the action of the spring 86, thus operating the cam 64 to raise the member 67. Further, rotation causes the roller 33 to rise to the top of the member 67, thus lifting the lever 32 and rocking the lever 25, 26 until the roller 27 carried by it engages the cam 28 and almost immediately strikes the valveoperating cam 29, so that the valve is closed and the conveyer stopped just as the latter completes one revolution. Another charger is then placed on the tray and the sequence of operations is continued until the first charger reaches the loading station. When this occurs the primary control of the motor is taken over by the feeler 39, the action of which is described in Specification 588,299. If it is desired to continue to feed the conveyer as the chargers are removed, the tray is moved by the crank 78 to tilt and cover the aper-. ture in the casing before a charger is placed on it. After a charger is placed on it, the tray is tilted by hand to allow the charger to enter the casing. If, however, the gunloader has just removed a charger, the conveyer will be in operation and tilting cannot take place since the roller 59 is riding on the concentric portion of the cam 61. Pressure .must, therefore, continue to be exerted on the tray until the roller comes on to the operative part of the cam.