US2693107A

US2693107A - Ski test bench

Info

Publication number: US2693107A
Application number: US204453A
Authority: US
Inventors: Frederick T Paden
Original assignee: Individual
Current assignee: Individual
Priority date: 1951-01-04
Filing date: 1951-01-04
Publication date: 1954-11-02
Anticipated expiration: 1971-11-02

Description

F. T. PADEN SKI TEST BENCH Nov. 2, 1954 Filed Jan. 4, 1951 INVENTOR I. Frecferck poon :wm-ME.

United States Patent SKI TEST BENCH Frederick T., Paden, Collingswood, N. J., assignor t0 the United States of America as represented by the Secretary of the Army Application January 4, 1951, Serial No. 204,453

6 Claims. (Cl. 723-89) (Granted under Title 35, U. S. Code (19,52), sec. 266) The invention described herein, if patented, may be manufactured by or for the Government for governmental purposes without the payment to me of any royalty thereon.

This invention relates to apparatus for testing the strength, shape and dimensions of skis.

If the manufacture of skis is to be undertaken on a mass production basis, obviously substantial uniformity must be realized. At the same time, it will be extremely desirable to speed up and facilitate inspection, which should take place at the factory to obviate the expense of shipping to the purchaser skis which will not pass inspection and hence must be returned.

The present invention aims to provide a practicable apparatus usable at a ski factory for inspecting skis for uniformity of dimensions and shape, and adapted to impose variable loads on the skis to test their exibility or resilience. Among the advantages of the invention are simplicity of construction, ease of operation or use, and the small amount of floor space required for the apparatus.

In the accompanying drawings forming a part of this specification,

Fig. l is an elevation of the preferred ski test bench, the ski being shown in dotted lines;

Fig. 2 is an end elevation of the test bench omitting the ski;

Fig. 3 is a perspective view on an enlarged scale of one 1c-1f thle ski-holding loops used with the test bench of Fig. 4 is a perspective on the scale of Fig. 3 of another form of loop used with the test bench.

Referring particularly to the drawings, the preferred form of test bench comprises an upright fiat board 10, which may be of plywood or other suitable material -secured to and supported by a pair of pedestals or standards 11, 12 which have braces 13, 14 respectively. If preferred, the flat board may be rigidly secured against a wall, in which case the pedestals or standards will not be required. A at horizontal ski-supporting shelf 15 is mounted by means of brackets 16 on the vertical board and extends preferably for the entire length'of said board. Shelf 15 may be about four feet above theffloor on which the pedestals stand, but obviously may be supported at any elevation which will meet the convenience of the operator using the test bench. If preferred, the brackets 16 may be made vertically adjustable (not shown) to facilitate raising or lowering of the shelf to accommodate its height to that of the operator. This shelf may be about eight or nine inches wide. It is used in checking the lateral shape of the ski, which is laid flat on it: if the ski is warped or twisted, such defect will be immediately apparent when it rests on the flat shelf. The camber of the ski is also checked. By means of a template 18, which is a thin, flat metal plate having perforations 19 by which it is secured flat against the board 10 as will be described, the flexibility characteristic can be ascertained. Template 18 is marked with paint or in other ways, as indicated at 20, to show the manufacturing tolerances. It 1s preferred that the exposed surface of the template be black, with white marks (not shown) for indicating the tolerances. It is also preferred that a single template be marked for skis of two different lengths, being turned upside down when short skis are to be tested, or vice versa. If desired, several dierently marked templates may be used.

To hold the template in position, also to support the ski when it is being flexed while under test, a pair of `.of 1000 inch pounds.V or more.

loops

21, 22 are used, each of which will loosely surround an end of a ski being tested. Each loop has two end prongs for insertion in sets of apertures in the board near its opposite ends. These sets of apertures register with the perforations 19 and are arranged in horizontally running pairs, the apertures of each pair being disposed in a vertical plane, and each pair being spaced uniform distances (e. g., 11/2 inches) from the pairs of holes on either side. The

loops

21, 22 may be adjusted longitudinally of the board 10 by insertion of their prongs in selected pairs of apertures, thus adjusting the support points to skis of different lengths. The approximate position of a ski supported by the loops is shown in dotted lines, Fig. l. Thin metal plates 25, 26 are screwed onto the board 10 a'nd have apertures registering with the holes in board 10; these metal plates provide escutcheons or protective shields for the apertures, preventing abrasion and disligurernent of the wooden board by the ends of the pronged loops, which must be removed and reinserted each time a template is to be turned over or changed.

The two

loops

21, 22 are of nearly the same construction, both being of heavy wire or a thin rod bent in the form of a loop with an opening amply large enough to admit an end of a ski. The ski is turned upside down for testing, and its toe end is inserted through loop 21 which has been previously mounted on the board 10, while its rear end is inserted through loop 22 at the opposite end of the board.

Loops

21 and 22 have metal blocks 27, 28 respectively through which the loop wire tached to the spring-supported member of a spring balance or scales 32. Said scales are slidably supported on a pair of parallel guides 33 removably xed to board 10 and extending vertically. A ring or other attaching means 34 fixed to the casing of the scales is attached to one end of a wire cable 35 which passes over

sheaves

36, 37 mounted at the top of board 10; and the wire cable extends down along the back of said board to and around a sheave or winch 38 which may be power-driven but is shown as turned by a handcrank 39, a worm 40, worm wheel 41, and shaft 42. Such a reduction gearing is advantageous in that it is irreversible. In actual practice the worm and worm wheel will be enclosed in a casing (not shown) containing lubricant. The ratio of reduction gear 40, 41 may be 30:1 or greater to give an output To prevent scarring of the ski nish, a rubber pad 43 having a' roughened or non-slip upper surface (not shown) is xed to that part of arm 30 which is in contact with the ski. The described construction will permit an operator by turning the hand crank 39 to impose a lateral stress of the desired poundage on the middle of the ski in a direction which is upward relative to the upside down 'ski and therefore downward relative to the normal position of the ski. A pair of graduated scales 44 are marked on the template near arm 30 so as to permit measurement of the vertical deection of the ski when under a certain load as indicated on the dial of the spring scales. Obviously, the spring scales will move upwardly when loaded, but the extent of such movement will be less than the displacement of the ski-engaging arm 30. Guides 33 prevent the spring scales when loaded from assuming any position other than a vertical position, while the rubber pad 43 and the two

loops

21, 22 prevent the ski from slipping of the arm when under a load. The

loops

21, 22 receive the ski ends loosely so that the ski is free to move slightly at said ends, as it must do when its normal camber is flattened by an imposed load. A test chart (not shown) may be attached to the at vertical surface of board 10 and may include legends and directions guiding the inspector using the test bench, so that he will know when to reject and when to accept a ski. If a.

certain number of inch pounds are required to flatten a ski of standard strength, obviously any wide departure from the standard of ilexibility should cause a rejection.

W'hat I claim is:

` 1. Apparatus for testing ski flexure comprising a support; plural means xed on the support for loosely supporting a ski near its ends with the ski turned upside down; an arm directly engaging the middle portion of the ski on the underside of the upside down ski; a spring balance having its spring pivotally supporting the arm from above; guide means xed on the support with which said spring balance slidably engages; a flexible powertransmitting member supporting the upper end of the spring balance; an operating crank; a reduction gear operated by the crank; and a sheave driven by the reduction gear, with the flexible member adapted to be wound around the sheave thereby to impose a measurable load on the ski through the intermediation of the spring balanceV and the arm.

2. Apparatus for testing ski exure comprising an upright support; a pair of loops mounted on the support and extending outwardly therefrom substantially at right angles and insubstantially the same horizontal plane, said loops being adapted to receive and loosely embrace the opposite ends of a ski placed upside down; an L- shaped arm engaging the mid portion of the upside down ski from underneath; a spring balance pivotally supporting the upper end of said L-shaped arm so that any pull on the arm is readable on the scale of the spring balance; guide means xed to the support and extending vertically; said spring balance having means slidably engaging said guide means; a wire cable from one end of which the spring balance is suspended; and means on the support affording a considerable mechanical advantage and operable by an operator to wind up the wire cable thereby to impose a load on the ski when held by said loops, said load being measurable on the spring balance.

3. The invention deined in claim 2, wherein there is a sheave at the upper end of the support, the Wire` cable being trained over said sheave and extending down alongside the back of the support, the means affording mechanical advantage consisting of a hand crank, reduction gearing driven by the hand crank, said reduction gearing being constructed and arranged so that the reaction of the load on the gearing is impotent to turn the hand crank, and a sheave driven by the reduction gearing, the wire cable being wound up on the last-mentioned sheave when a load is to be imposed on the ski.

4. Apparatus for testing ski flexure comprising a support; plural means fixed on the support for embracing and loosely supporting a ski near its ends with the ski turned upside down; means on the support to hold said plural means in adjusted positions to accommodate skis of different lengths; means movably mounted on the support for engaging the ski substantially midway between said supported ends, said ski-engaging means consisting of an arm contacting the ski in the region where the foot of the user normally rests; means aiording a considerable mechanical advantage and mounted on the support and operated by the operator for imposing a load on the ski by upward movement of the ski-engaging means against the upside down ski on said support; means to measure the imposed load consisting of a spring balance which pivotally supports the upper end of said arm so that any pull on the arm is readable on the scale of the spring balance; and a graduated scale xed on the support in such a position that a measurement may be made of the extent of exure of the ski when so loaded.

5. Apparatus for testing skis comprising an upright support; ski-supporting means xed to the upright support, said ski-supporting means holding the ski in horizontal position and being constructed and arranged to permit longitudinal movement of the supported ski in response to flexing; a template having markings thereon for indicating manufacturing tolerances; means to secure the template to the upright support with the template lying vertically so that the ski when flexed by a predetermined load may be viewed against the markings on the template; and operator-controlled means on the support for imposing transverse loads on a ski supported by said ski-supporting means.

6. Apparatus for testing ski flexure comprising an upright support; a marked template fixed vertically on and lying at against said support; removable means to holdV the template removably on the support, said removable means consisting of a pair of loops each adapted to receive and loosely surround an end portion of a ski, each loop having end prongs; the upright support having two horizontally extending and horizontally aligned series of apertures adapted to receive the end prongs of the loops; the template having registering apertures and the loops holding the template in place when their prongs are inserted in the apertures; one of said loops carrying a stop against which an end ofy the ski abuts to prevent longitudinal movement of the ski in one direction, the other loop being open to permit longitudinal movements of the ski in either direction responsive to lateral flexing of the 1s ki lnder imposed loads and after such loads are releve References Cited in the file of this patent UNITED STATES PATENTS OTHER REFERENCES Oil and Gas Journal, vol. 42, No. 4, lune 3, 1943, PP. S13-46, by G. D. Kish, in the Engineering and Operating ection.