Patent GB-476070-A (GB)
Title: Improvements in and relating to machines for grading leather blanks according to edge thickness
IPC: B07C5/12
Filed: 1936-08-18
Abstract: 476,070. Linear - dimension gauges. BRETHOLTZ, N. Aug. 18, 1930, No. 22705. [Class 106 (ii)] In a machine for gauging the minimum edge thickness of sole blanks a pair of measuring arms swung about fixed axes carry measuring devices and follow the contour of the sole while allowing the measuring devices to move parallel to the pivot axes of the arms. Each measuring arm 22, of which there are two, is mounted on a pivot shaft 23 and urged by a spring 25 towards a central position determined by engagement with a stop 27. An extension 29 of the arm ends in a guide foot 30, Fig. 6, which engages the edge of a blank passing through the machine and causes the arm 22 to follow the contour. Pivoted to the arm 22 at 32 is a lever 31 pivoted at 33 to a vertical arm 34 carrying at its lower end on ball bearings the rotating bearing portion of a castor measuring roll 39 the rotation of the castor member which is offset relatively to the bearing point of the roller being limited by a stop. The vertical member 34 is pivotally connected at 46 with the measuring lever 47 pivoted at 48 to the arm 22. Vertical movements of the roll 39 are thus transmitted to the lever 47. A rod 50 is urged by a light spring 52 to force the roll 39 against a blank passing over a base measuring plate 52b carried by a roll 52c. The castor arrangement minimizes frictional rubbing and aligns better with the edge of the blank, the roller being mounted on a self-aligning bearing. Working. The blank enters the machine at the left hand, Fig. 2, passes under a gate 112 which is in the raised position, and under a roll 77 carried by a long lever 57 pivoted at 56 which it raises against the influence of a spring 75. A vertical lever 60 carried by a stub shaft 59 on the end of lever 57 is thus raised and tilts a lever 61 to move a pin 64 against the lever 47 and thus raise the castor roll 39. At the same time through an arm 79 connected to the lever 61. and a rod 80 a member 83 on lever 73a pivoted at 67 is moved down to engage a lug 84 on the castor and lock it against swivelling movement. The blank passes next under a roller 70 and lifts it turning the bell crank 68 about a pivot 71 at the end of an arm 73a pivoted at 74. This bell crank is also pivoted at 67 to levers 66 and moves these to the right, Fig. 2, pushing lever 60 from under lever 61 and allowing the lever 47 to rise and the measuring roll 39 to drop, unlock, and engage the blank. The blank passing under roll 72 raises it and moves the rod 108 to rock lever 102 and move stop 107 away from the pawl 103 allowing it to engage the ratchet lever 95. This movement through rod 110 also lowers the gate 112 and prevents entry of. another blank. The ratchet lever 95 is pivoted loosely on the indicating shaft 93 and is connected by a strong spring with a similar lever behind the lever 95, and fixed to the shaft 93. The teeth on the lever 95 allow movement in the direction of indicating greater thinness only while the other lever provided with oppositely sloped teeth allows movement in the direction of greater thickness only. The movements of the measuring lever 47 are transmitted by a rod 90 to the shaft 93. Just in advance of the measuring roller 39 is a foot 115 connected to a block 116 loosely pivoted on the shaft 76 of roller 77 which is cut away to accommodate the foot. The latter is also pivotally connected by rod 118 to a block 120, Fig. 19, loose on shaft 103a and carrying a spring pawl 124 and stop 126. When the foot is raised by a blank, the pawl 124 is moved by stop 126 away from the ratchet 96. When the blank has passed and measurement has finished, the pawl 124 is moved to engage its ratchet and thus hold the reading on the indicator. In a modified construction of locking pawl, when the pawl engages a tooth it makes an electric circuit and causes one of a series of lamps to light up, thus indicating a line corresponding to the thinness indicated, the sole being taken and thrown into that bin. The rolls 19, 20, 21 are driven by chain and belt gearing from a motor.