| 摘要 |
<p>The device comprises a guide bar 10, two sliders 12, 14 mounted on the bar 10 and each carrying a handle 16, 18, and two guide units 51, 56, one at each end of the bar 10. A tape 20 runs in a loop between the two guide units 51, 56 and is connected to the sliders 12, 14 so that they move either towards or away from each other. Tensioning means, provided in slider 12 (see Figures 2 & 3), maintains a tension in the tape 20 so that movement of the handles 16, 18 causes the tape 20 to slide frictionally over the guide units 51, 56. <IMAGE></p> |
