US1984233A - Hygroscope - Google Patents

Description

R. F. REED Dec. 11; 1934.

HYGROSGOPE Filed June 2, 1931 2 Sheets-Sheet 1 'WXM W76, ATTORNEYS R. F., REED HYGROSCOPE Filed June 2, 1931 Sheets-Sheet 2 Jim WE Iii/7m INVENTOR ATTORNEYS Patented Dec. 11, 1934 UNITED STATES HYGBOSCOPE Robert F. Reed, Norwood, Ohio, assignor to The lithographic Technical Foundation, Inc., New York, N, Y., a corporation of Delaware Application June 2, 1931, Serial No. 541,040

5- Claims. (01. 13-24) This invention relates to an article adapted to indicate the degree of variance between the moisture content of air entrained in a pile of paper and the moisture content of the atmosphere surrounding the pile of paper.

Attempts have been made in the past to measure the moisture content of paper in the pile by means of a hygrometer designed to read. in terms or percentage relative humidity or percentage moisture. Hygrometers actuated by hygroscopic elements possess the disadvantage in that the hygroscopic element tends to stretch as a result of prolonged usage with the result that a cumulative error in the readingsisdeveloped. The concept of, this invention is to provide a paper hygroscope adapted to indicate whether or not pilesof paper are in a condition of hygrometric equilibrium with the atmosphere of the work roomin which they are handled.

The instrument, therefore, is intended and adapted not to provide readings in terms or moisture content, but to indicate the humidity of the pile of paper inrelation to the existing humidity of the atmosphere of the room. By .this method one may obtain accurate information from day to day whether or not the piles 01' paper to be used are in proper condition for working without having the calculations subject to errors resulting from change of condition or elasticity of the delicate hygroscopic element.

This instrument should be of particular value to lithographers and printers who operate sheetied presses. It is not a hygrometer and gives no reading in terms of moisture content or relative humidity. a

The object of the invention is to provide an accurate instrument of the nature heretofore described, properly constructed and proportioned to indicate deviations in moisture content and provided with indicating mechanism of a type adapted to be most easily readable for informing the user whether or not there is hygrometric equilibrium between the atmosphere of the work room and the paper to be handled. Other objects and further advantages will be more fully apparent from a description of the accompanying drawings, in which:

Figure '1 is a side elevation of the hygroscope. Figure 2 is a sectional view taken on line 2-2, Figure 1, illustrating the construction of the blade and arrangement of the hygroscopic element and its connection to the indicating hand operating mechanism at the handle.

Figure 3 is a perspectiveview generally lllustrating the moisture sensitive or hygroscopic actuating element.

' Figure 4 is a sectional view taken on line 4-4, Figure 1, detailing the arrangement of the tape in the blade connecting the actuating element and the transmission at the indicating hand.

Figure ,5 is a sectional view taken on line 5-5, Figure 1, detailing the arrangement of the actuating or'moisture sensitive element within the blade.

Figure 6 is a fragmentary iront view of the portion of the'hygroscope at the dial casing, the dial being removed for illustrating the indicating hand motion increasing means.

Figure 7 is a sectional view taken on line 77, Figure 6; further illustrating the motion transmitting and increasing mechanism between the moisture sensitive element and the indicating hand as wellas the'movable dial.

Figure 8 is a fragmentary view taken similar to. Figure 6 but showing the dial casing entirely removed for illustrating the coil spring tensioning the hygroscopic element and balancing or stabilizing .the indicating hand.

Figure 9 is a sectional view taken on line 9--9, Figure 6, further detailing the motion transmitting and increasing mechanism.

, Figure 10 be general fragmentary view illustrating a stack of paper with the hygroscope placed in position between the sheets thereof for determining the difference in moisture content of the paper and the humidity of the room.

The hygroscope consists of a sword-like blade which can be inserted between the sheets in a pile of paper 16 (see Figure 10). A movable -hilt 17 is provided to regulate the'distance to which the blade is inserted and to cover the opening in the pile. The blade carries a partially enclosed hygroscopic element 18 which is connected by means of metal tape 19 to a pulley 20 which actuates an indicating hand 21 through a motion increasing mechanism. A movable dial 22 is provided for the purpose of facilitating accurate observation or the movement of the indicating hand. The pulley, motion increasing mechanism, indicating hand, and dial are contained in the external handle 23 of the instrument.

The hygroscopic element preferably comprises gold beaters skin on which a pull such as 100 grams, is exerted.

Multiplying mechanism is used to translate stretch and shrinkage of the hygroscopic element, as transmitted by the connecting metal spacer annulus 42 by an upper annulus 43, the

tape, into rotation of the indicating hand in such manner that a 5% change in relative humidity of the atmosphere surrounding the hygroscopic element, in the range between 45 and 55% relative humidity, will cause the hand to rotate through an angle of 30.

The blade 15 is of hollow structure for containing the moisture sensitive element or actuating element 18. It has a sharp point for ready insertion of the blade between sheets of a pile of paper and its general cross sectional contour is relatively fiat with rounded side edges.

The blade is preferably elliptical or substan tially so in cross section whereby the weight of the paper can be more uniformly distributed over its surface and perfect contact assured with no possibility of air passage between the blade and paper. Moreover, the danger of tearing and abrasion of the surface of the paper is minimized.

The hygroscopic element or moisture sensitive element is composed'of a strip of gold beaters skin having its ends bound by fabric strips 24 adhesively or otherwise attached in overlapped position. Eyelets 25 are provided at the respective ends of the element, being formed of wire having central eyelet portions and side extensions contained within the bight of the overlapped fabric, the eyelet protruding through an aperture in the fabric centrally of the ends of the element. The element thus formed is mounted within a longitudinal channel 26 within the blade and is extended as nearly ad- J'acent the tip of the blade as possible. At the sides of the channel or element 18 the blade is open to the atmosphere or the paper through a series of openings 27 disposed along the blade sides. At one side the apertured wall is removable, being in the form of a ported plate 28.

The outer end of the hygroscopic element 18 is.fixed to be blade by means of 'a screw 29 extending through the eyelet into the blade. At the inner end of the hygroscopic element 18 the end of a steel tape or wire 19 is attached thereto, this tape or wire extending through a narrow slot or channel 30 in that side of the blade adjacent the removable plate and having its end attached to the grooved pulley 20 journalled within a chamber 31 formed in the handle portion of the instrument.

This pulley 20 is fixed to a shaft 32 journalled in the handle, which shaft also has a large gear 33 fixed thereto and meshing with a small gear 34 fixed to a shaft 35 which is concentric with the dial casing. This centrally disposed shaft carries the indicating hand 21. The circular dial casing 36 is attached upon the handle by means of a plurality of screws 37 extending through the bottom of the dishlike dial casing 36 and into a plate 38 seated in a rectangular recess 39 on the opposite side of the handle element, spacers 40 being provided between the bottom of the casing and the disk within the chamber 31 previously mentioned, the, screws therefor clamping the casing 36 and plate 38 in position.

- The shafts mentioned have their inner ends journalled in the plate 38 and their upper ends journalled in disks 41: fixed intermediately of the depth of the casing. These disks within the casing are secured in spaced relation to the bottom of the casing by means of a spacer annulus 42 fitting within the circular casing below the same and are held in position against the movable dial 22 or glass disk being mounted upon the top of this upper annulus. The annuli 42, 43, the metal disks 41 and the dial or glass disk 22 are maintained in position by means of a collar 44 screwed upon the casing and having a flange 45 overhanging the dial or glass disk 22.

The indicating hand 21 is fixed to the central shaft 35 between the metal disk and the glass disk so as to be visible through the glass. The transmission and hygroscopic elements are placed under a tensioning and stabilizing force by means of a clock spring 46 having its inner end fixed to the central shaft 35 and its outer end attached -to one of the casing securing spacer elements 40. Undueoutward spring of the clock spring is prevented when the same is relaxed by'engagement thereof with another of the casing anchoringspacer elements 40. The spring is eifective for placing the hygroscopic element 18 under a normal pull of 100 grams, assuring a constant tautnessthereof.

It will be seen that the position of the indicating hand is determined by the contraction and expansion of the hygroscopic or moisture sensitive element in the blade since the most minor or almost unnoticeable change in the length of this element will be effective for actu. ating the transmission and the movement will be increased through the large gear meshing with the small gear for increased movement of the -indicating hand proportionate to the expansion and contraction movement of the sinsitive element. Therefore, its position will be a variable one, depending on the atmospheric conditions surrounding the instrument;

To determine the change .or fluctuation of the hand, due to expansion or contraction of the hygroscopic element, the glass disk or dial 22 is manually rotatable within the casing, operation being accomplished through a knob 47 secured to the glass adjacent 'the periphery thereof by means of a screw 48 extended into the knob from the inside of the glass. The dial 22 has felt washers 49 above and below-for securing it against normal displacement but permitting rotative manipulation.

This glass dial or disk 22 has a plurality of markings on its peripheral margin on the under side thereof. These consist of three indicating points or arrows, the intermediate of which, namely 50, is adapted to be registered with the indicating hand and the outer of which, namely 51, are each spaced 15 from the intermediate and are limit indicating points. Beyond these points the periphery is suitably marked as at 52 to identify further degrees of indicating hand variation from the intermediate marking.

The adjustable hilt 17 is secured in position on the blade for limiting blade insertion as determined by the width of the paper pile by means of the set screw 53. It is preferable that the blade extend to the center of the pile for accurategeading.

In operation, the operator'first satisfies him- .self thatthe hygroscope is atv equilibrium with the atmosphere of the room. He does this by setting the central or intermediate indicating point on the movable dial opposite the indicating hand and swinging the instrument in the air for one minute. If the central or intermediate indicating point is not still opposite the indicating hand, he resets it to this point and repeats the 7 operation until the registration of the indicating hand with the intermediate point is approxthan that bounded by the intermediate indicat-,

masses \1 imately maintained during one minute. He next insertsthebladeinthepileofsheetstoflie desired distance and notes whether or not the indicating hand rotates through an are greater ingpointoithedialandoneoitheadjacent limit indicating points within a period of two minutes.

It the, indicating hand does not pass either of the limit indicating points, the papermay be safeLv printed without further conditioning ,under the existing atmospheric conditions. If; however, the indicating hand passes either of the limit indicating points, the paper should be conditioned to the pressroom atmosphere before Printing. Having described the invention, I desire to be limited only by the following claims: v 1. 4 hygroscope, comprising, a hollow apertured blade, a hygroscopic element disposed in said blade, means for maintaining said element in taut condition, an indicating device, a trans-1 mission mechanism for actuating said indicating device, a connecting element of metal tape between said hygroscopic element and said transmission mechanism, wherebythe transmission mechanism is capable oi magnifying the expansion and contraction movements of the hygroscopic element for causing the indicating device to show plus or minus deviations from a known or determinable moisture content.

2. A hygroscope adapted to be inserted between sheets ot a pile of paper comprising, a

hollow apertured blade, an adjustable hilt mounted on said blade, -a hygroscopic element mounted in said blade, said blade having curved surfaces for maximum contact with the paper, and an indicating means on the handle of the blade connected to said hygroscopic element for 40 showing the variation between conditions of humidity in the room and in the paper pile. 3. A hygroscope, comprising, a hollow apertured blade adapted to be inserted between the sheets of a pile of paper, a handle for said' blade,

5 a hygroscopic element longitudinallydisposed within the blade toward the outer end thereof, said hygroscopic element composed of a moisture sensitive sheet of material readily expansible and contractible, a motion increasing trans- 50 mission connected to said moisture sensitive ele- V a ment for increasing and converting the move ment derived therefrom into rotative movement,

an indicating hand connected to and actuated by said transmission, tensioning means in the transmission for maintainingthe hygroscopic element in taut condition and the indicating hand in stabilized normal position, and an adjustable marked dial movable relative to the indicating hand for initially setting a mark relative to the indicating handwhen the hygroscope is exposed to atmospheric conditions in'the room whereby variations thereim when the hist .scopeisinpositionoiusemaybeindicatedby movement of the said mark;

4. A hygroscope, comprising, a hollow aperindicating hand relative to tured blade adapted to be inserted between the sheets of a pile of paper,'a handle ior said blade, a hygroscopic element disposed within the blade toward the point thereof, said hygroscopic element composed of amoisture sensitive sheet 01' material readily expansible and contractible, a

motion increasing transmission connected to said eating device, a connection between said motion increasing transmission and said hygroscopic element, and means for maintaining said hygroscopic element in taut condition, whereby the transmission mechanism is capable of magnifying the expansion and contraction movements oi the hygroscopic element for causing the indicating device to show plus or minus deviation from an initial setting. A

ROBERT F. REED.

creasing transmission for actuating said indi-

Images