Specification of Thomas Adams : trusses.

  • Adams, Thomas.
Date:
1857
Catalogue details

Licence: Public Domain Mark

Credit: Specification of Thomas Adams : trusses. Source: Wellcome Collection.

    5/8 (page 3)
    Adams Improvements in Trusses, dfC. spring, as represented in Figure 1. But I do not confine myself to this mode of construction, because the said additional spring may also be applied and connected to the inside of the main spring. The strap attached to the addi¬ tional spring may slide or move within the covering of the truss by the ends of 5 the said strap coming through holes or other apertures in such covering; and upon one of the projecting ends of such strap I introduce my second improve¬ ment, which is a graduated scale, with figures upon it for the purpose of thereby showing the increase or decrease of pressure that takes place in pounds, ounces, or other denominations of weight; and I obtain the divisions 10 to be marked upon the strap, as shown at Z, Figure 1, by opening the truss to the extent which it would have in wear, and then suspending the different weights from the centre of the pad while the aforesaid additional spring is moved into its various positions. If a stud should be preferred to a strap for moving the said additional spring, then the said gradation or scale of force 15 may be made on the side of the slit or opening in the covering through which the said stud or handle slides. Figure 2 shews the spring of a common single steel truss curved or rounded in or near to the usual and ordinary manner, a, a, a, a, are slits herein¬ before mentioned to be made for the screws or rivets of my said additional 20 spring to slide therein. Figure 3 is the additional spring, tapering a little to one of its ends, and b, b, are rivets or screws for the purpose of connecting Figure 2 to Figure 3 by passing through the slits a, a, a, a, in Figure 2, and into the holes c} c, in Figure 3. 25 Figure 4 represents the edge of Figure 3, and thereby shews the degree of rounding or curving generally necessary for the latter before its connexion with or application to Figure 2; but the additional spring maybe more or less curved or straight, as may be found sufficient to controul or regulate the pressure of the main spring, and best adapt the truss to the shape and purpose 30 for which it may be required ; the additional spring may also be made in one or more part or parts, but a single additional spring will generally be sufficient to regulate the pressure of a single truss. When the additional spring is required to be connected with a double spring truss or an umbilical spring truss or two single spring trusses forming a double spring truss, then two of the additional 35 springs will generally be necessary, one being placed upon the right and the other upon the left side of the main spring on such truss, there being in each of these cases two parts of the main spring to be acted upon by the additional spring. It will be observed in the above description, and by reference to Figure 4