US3788577A

US3788577A - Pneumatic tube carrier end closure construction

Info

Publication number: US3788577A
Application number: US00208756A
Authority: US
Inventors: C Barnett; L Morrison
Original assignee: Diebold Inc
Current assignee: Diebold Nixdorf Inc
Priority date: 1971-12-16
Filing date: 1971-12-16
Publication date: 1974-01-29
Anticipated expiration: 1991-01-29

Abstract

A closure construction for an open end of a generally tubular material-conveying carrier for a pneumatic tube system, especially adapted for banking service transactions. The end closure, preferably is formed of lightweight molded plastic components, and is pivotally mounted for smooth and ready lateral movement across an open end of the carrier body between fully closed and fully open positions. The end closure side wall is tapered enabling the carrier to move through pneumatic tube bends having reduced radii. An inturned flange is formed on the end closure and engages an outturned flange on the carrier body when in closed position preventing axial movement of the end closure away from the carrier body. A spring-biased toggle-connected mechanism is contained in a cavity formed within the end closure to urge and hold the closure in either fully closed or fully open position.

Description

itd States Patent [191 arnett et al.

[ PNEUMATIC TUBE CARRIER END CLOSURE CONSTRUCTION [73] Assignee:

[52] US. Cl. 243/35, 243/39 [51] Int. Cl. B65g 51/06 [58] Field of Search 243/35; 220/38, 41, 55, 33

Primary Examiner-Evon C. Blunk Assistant Examiner-James L. Rowland ABSTRACT A closure construction for an open end of a generally tubular material-conveying carrier for a pneumatic tube system, especially adapted for banking service transactions. The end closure, preferably is formed of lightweight molded plastic components, and is pivotally mounted for smooth and ready lateral movement across an open end of the carrier body between fully closed and fully open positions. The end closure side wall is tapered enabling the carrier to move through pneumatic tube bends having reduced radii. An in- [56] References Cited turned flange is formed on the end closure and engages an outturned flange on the carrier body when in UNITED STATES PATENTS closed position preventing axial movement of the end 3,556,436 1/1971 Roelandt 243/39 closure away f the carrier body A spring biased fi g toggle-connected mechanism is contained in a cavity 34268l3 2/1969 z z 'gg 220/33 formed within the end closure to urge and hold the closure in either fully closed or fully open position.

FOREIGN PATENTS OR APPLICATIONS 1,102,049 3/1961 Germany 243/32 7 Clam, 11 Drawmg F'gures 52 I 39. 51 53 44 9 12 i t 11 I "L 7 42.2 Sufi; 43

. 1 I I 6 i l A 14 BACKGROUND OF THE INVENTION RELATED APPLICATIONS The invention involves improvements upon the carrier closure construction shown in the copending application of Walter G. Anders et al., US. Pat. Ser. No. 63,233, filed Aug. 12, 1970, which issued Oct. 31, 1972 as US. Pat. No. 3,701,497.

1. Field of the Invention The invention relates to a carrier for materials which move through a pneumatic tube and especially to noncaptive pneumatic tube system carriers used in performing banking services between a teller station and a remote customer station. More particularly the invention relates to an improved end closure for a hollow carrier body readily movable between fully open and fully closed position, in each of which positions the closure is held securely.

2. Description of the Prior Art Many closure arrangements for pneumatic tube system carrier access openings have been used. Frequently the mounting and latch mechanisms for carrier closures have been complicated and subject to injury and wear in use. The structure of the end closure shown in the copending application satisfies requirements as to simplicity, wear and frictional problems which develop between relatively movable parts of the control mechanism. i

It is becoming increasingly more important in the design of pneumatic tube systems to reduce the size of the bend radii in the pneumatic tubes through which carriers move, without the carrier becoming lodged, damaged or losing propelling force, and without reducing the interior volume or load carrying capacity of the carmen This may be accomplished by tapering the carrier ends such as shown in said copending application. However, this results in a smaller carrier end opening and reduces the effective carrier storage volume. It also reduces the size of the material which may be inserted into the carrier, and makes it more difficult for manually removing material lodged or held within the carrier.

It is desirable to reduce the weight of the carrier end closure to prevent premature opening of the end closure during movement through the tubes by centrifugal forces which may act on a heavy end closure during travel at high speed through a tube system. This heretofore has presenteda problem. Reduced weight may be obtained by molding the end cap components of lightweight, rugged plastic material. Reducing the weight of the end closure by use of plastic material results in wear and friction problems between the relatively movable parts of the pivotal mounting andcontrol mechanism. Prior wear and friction must be reduced for satisfactory carrier operation.

Thus, the need exists in the art for a rugged, simple, lightweight carrier end closure construction which enables carriers to pass through tube bends having smaller radii of curvature then heretofore possible with prior carriers, without a reduction in carrier storage capacity or end opening diameter; which end closure can be readily opened and closed without binding and without excess friction, and which can be effectively held in either position with full access to the carrier when opened.

SUMMARY OF THE INVENTION Objectives of the invention include providing a pneumatic tube system carrier with a closure for its end opening that may be moved readily without binding between open and closed positions; which eliminates latches and reduces friction and wear; which is effec tively held in fully closed position when closed and in fully opened position when open; which has stop means on the carrier walls to prevent further opening movement of the end closure when in open position to prevent damage to the end closing control mechanism; which is tapered to enable smaller radii pneumatic tube bends to be used in a pneumatic tube system without the storage capacity or the open end diameter of the carrier body being reduced; which is lightweight preventing premature opening due to centrifugal forces acting on the end closure during transit; which is formed inexpensively of molded plastic components easily assembled, together with a control mechanism of an inherently bistable nature and of togglearrangement, so as to'urge the closure to hold the closure in either fully opened or fully closed positions; which has flanges engageable with the carrier body when in closed position preventing axial separation of the end closure from the carrier body; and which is simple in construction and operation, and composed of rugged parts not subject to fatigue failure from use and .which can withstand severe shocks.

These objectives and advantages are obtained by the pneumatic tube system closure construction for carrier access openings, the general nature of which may be stated as including a generally tubular, preferably transparent plastic material carrier body having two ends and open at least at one end; closure means for said open end, and means pivotally mounting the closure means on the body for lateral movement of the closure means across the open end between fully opened and fully closed positions; the pivotal mounting means including a pivot shaft fixed to the body having an axis, and means journaling the end closure means on said pivot shaft; the end closure means including an end cap and a disc member having cavity and bottom faces; the end cap having top and side walls forming a cavity into which an end of the pivot shaft extends; means securing the disc member-to the end cap to close the cavity; the end cap side walls being tapered downwardly and outwardly from the top wall; spring-biased, toggle control means located in said end closure cavity urging the closure means towards and holding said closure means in either fully open or fully closed position; the open end portion of the carrier body wall having first and second connected curved sections; the first section being arcuate and having a shorter length than the second section; the first section projecting axially beyond the end of the second section; the projecting first section terminating in stop shoulders, one of which is arcuately aligned with an arcuate portion of the second section and the other of which is offset laterally outwardly of the arcuate section; a curved laterally outwardly projecting flange formed on the second section adjacent said offset shoulder; the end closure means having an arcuate flange segment extending axially below the bottom face of the disc member; a laterally inwardly projecting flange at the free edge of said flange segment spaced from the bottom face of the disc member and forming therewith an annular groove; the end of the flange segment providing shoulders one of which is engageable with the offset body shoulder when the closure means is in closed position; the curved outwardly projecting body flange being seated in said annular groove when the closure means is in closed position; the closure means having an annular segmental recess formed therein extending above the bottom face of the disc member; said segmental recess extending circumferentially of the closure means away from said one flange segment shoulder; and said segmental recess receiving and overlying the projecting first body section.

BRIEF DESCRIPTION OF THE DRAWINGS A preferred embodiment of the invention illustrative of the best mode in which applicants have contemplated applying the principles is set forth in the following description and shown in the drawings and is particularly and distinctly pointed out and set forth in the appended claims.

FIG. 1 is a perspective view of a carrier provided with the improved end closure construction;

FIG. 2 is an end view of the carrier shown in FIG. 1, with parts broken away;

FIG. 3 is a view similar to FIG. 2, showing the closure in partially open position in dot-dash lines, and in fully open position in solid lines;

FIG. 4 is a fragmentary sectional view taken on line 44, FIG. 3;

FIG. 5 is a fragmentary sectional view taken on line 55, FIG. 2, showing the journal pivot mounting of the end cap on the housing pivot shaft;

FIG. 6 is an enlarged fragmentary sectional view taken on line 6-6, FIG. 5;

FIG. 7 is a fragmentary elevational view looking in the direction of arrows 7-7, FIG. 3, showing the carrier body closure flange;

FIG. 8 is a fragmentary bottom plan view of the end closure removed from the carrier body;

FIG. 9 is a fragmentary sectional view taken on line 99, FIG. 5;

FIG. 10 is an enlarged fragmentary, elevational view looking in the direction of arrows 10-10, FIG. 3; and

FIG. 11 is a fragmentary sectional view taken on line l111, FIG. 3.

Similar numerals refer to similar parts throughout the drawings.

DESCRIPTION OF THE PREFERRED EMBODIMENT The improved pneumatic tube system carrier 1 (FIG. 1) has a carrier body 2 formed by cylindrical side wall portions 3 and generally flat side wall portions 4. A plurality of spaced reinforcing ribs 5 are formed integrally with and extend along wall portions 3 between enlarged cylindrical end portions 6.

Body 2 may have either one or two open ends, two open ends 7 being provided for the carrier 1 illustrated. Each open end is closed by an end closure 8 which forms the closure means for the carrier.

An annular shoulder 9 (FIG. 5) is formed on each end portion 6 and an accelerator ring 10 is mounted thereon and surrounds body 2. A collar 11 is pressfitted over and preferably bonded to each end portion 6 and retains rings 10 on shoulders 9.

Each end closure 8 includes a disc member 12 and a cap 13 is secured to the disc member 12 in any suitable manner as by a screw 14. Disc 12 and cap 13 preferably are molded of lightweight, rugged plastic. Disc 12 is formed with an outer annular rib 15 which engages an annular shoulder 16 formed on cap 13 (FIGS. 5 and 11) when joined by screw 14.

In accordance with the invention the side wall 17 of cap 13 is tapered and forms and internal control mechanism cavity 18 with top wall 20. Disc 12 closes the bottom of cavity 18 and has cavity and bottom faces or surfaces, 12a and 12b, respectively. An external recess 19 is formed in the top wall 20 of cap 13 providing a finger hold accessible for opening and closing end closure 8.

Carrier body 2 has a thickened wall portion 21 (FIGS. 5 and 6) adjacent open end 7 formed with an axially extending bore 22, enlarged at 23 in which a pivot shaft 24 is fixed by a retaining pin 25. A lug 26 is mounted on the outer end of shaft 24 and projects laterally of a diametric line 27 passing through the axis of shaft 24 and the axis of body 2 as shown in FIG. 2. Lug 26 forms a shoulder 28, and the offset portion 29 of lug 26 is formed with an opening 30 located eccentrically with respect to shaft 24.

Disc member 12 has a pivot sleeve 31 formed integrally therewith which is telescoped over the pivot shaft 24 when the parts are assembled as shown in FIG. 5. In assembled condition, lug shoulder 28 engages a washer 28a which is recessed in the surface 12a of disc 12 within the cavity 18. Shoulder 28 holds disc 12 and connected cap 13 assembled to carrier body 2 when the retaining pin 25 engages pivot shaft 24.

Thickened wall portion 21 and pivot sleeve 31 both preferably are formed of plastic. A metal bushing 33 is inserted into enlarged bore portion 23 so that pivot sleeve 31 pivots within bushing 33. The pivoting movement of metal-on-plastic and vice versa is much more desirable than plastic-on-plastic and provides reduced friction and less binding.

In this manner, pivot sleeve 31 is telescoped within metal bushing 33 which is located in the enlarged bore 23 in body 2 and is journaled on pivot shaft 24, and lug 26 is located in cavity 18 formed in end closure 8.

End closure 8 thus is pivotally mounted for lateral movement across the open end 7 of the carrier between fully open position shown in FIGS. 3 and 4 and fully closed position shown in FIGS. 2 and 5; such lateral pivotal movement occurring about pivot shaft 24 as an axis. During such pivotal end closure movement, lug 26 and offset portion opening 30 remain in a position fixed with respect to the carrier body within end closure cavity 18.

Action of end closure 8 is controlled by a compression coil spring 34 which surrounds a rod 35. One end 36 of rod 35 is formed with a slight U-shape and extends through ofi'set opening 30 and is pivotally mounted therein. The opposite end 37 of rod 35 extends slidably through a knuckle cap 38 which is held within end closure cavity 18 by

projections

39 and 40 which are formed on disc 12 and cap 13, respectively, and which extend into cavity 18 (FIG. 4).

Spring 34 extends between knuckle cap 38 and a collar 41 found on rod 35 adjacent lug 26. Spring 34 is compressed as end closure 8 is pivoted counterclockwise about pivot shaft 24 from the position of FIG. 2 toward that of FIG. 3, and the compressed spring of the spring-biased, toggle-control mechanism moves end closure 8 either to fully opened or fully closed position in accordance with toggle operation.

Rod end 37 slides through knuckle cap 38 in cavity 18 as end closure 8 is being rotated between open and closed position, as shown in dot-dash line, FIG. 3, due to the eccentrical location of offset opening 30.

The structural relationship described of the end closure 8, body 2 and the spring-biased, toggle-control means imports a torque to end closure 8 so that closure 8 has only two stable positions, either fully opened or fully closed, as shown..This bi-stable nature of the end closure and its control mechanism maintains the end closure 8 in positively closed position when closed, for reliable protection of the carrier contents as it moves through a pneumatic tube; and also insures that when opened, the closure is held fully opened for convenient loading and unloading of the carrier contents.

Each body-end portion has another slightly thickened wall portion 42 (FIGS. 3, 5 and 9) axially aligned with the flat side wall portions 4 and located diametrically opposite thickened wall portion 21. Thickened portions 42 preferably are formed by a plurality of spaced elongatedinternal ribs 43 which provide sufficient strength for end portions 6, and reduces the weight of carrier body 2.

The improved sealing and interlocking ability of the carrier end closure is achieved by the particular structures of end closure 8 and carrier body end portions 6 and their interengagement with each other.

Each end wall portion 6 of carrier body 2 terminates in

curved sections

44 and 45. Section 44 is arcuateshaped and generally is the end of one carrier cylindrical body wall. portion 3..- Section 45 includes

portions

46 and 47. .Wall portion 46 also is an extension of the other cylindrical body wall portion 3 andof the outer end of thickened wall portion 21. The second portion 47 of curved section 45 is curved on a larger radius than portion 46 and extends in chord-like fashionj between curved section 45 and portion 46 as illustrated in FIG. 3. Portion 47 projects outward axially from the thickened wall portion 42. Section 44 has a shorter arcuate length than arcuate portion 46 and projects axially beyond the' end of section 45, as shown in FIG. 7. The diameter of cylindrical open end 6 extends between terminal endsections 44 and 45 with. the radius of curvature of section 44and'arcuate portion46 being equal as indicated in FIG. 3.

Section 44 terminates in stop shoulders 48 and 49. Shoulder 48 is arcuately aligned with arcuate portion 46 and serves as a stop for endclosure 8, when closure 8 is in open position (FIGS. 3 and Shoulder 49'is offset laterally outwardly of curved portion 47and may serve as a stop for end'c losure 8, when closure 8 is in closed position (FIGS. 1 and7).

A curved flange 50 is formedon and projects laterally outwardlyfrom portion :47 overhanging and spaced from a portion ofthe end surface 51 ofthickened end portion 42 and terminates within the peripheryofcylindricalopen end 6 defined by curved sections 44 and 45 (FIGS. 3 and 5). One end 50a of flange 50terminates at offset shoulder 49 and the other end 50b terminates adjacent arcuate portion 46, (FIG. 7).

An arcuate flange segment 52 is formed on end closure 8 and extends axially below the bottom face 12b of disc member 12 (FlG.4). Alaterally inwardlyprojecting flange 53 is formed at the'free edge of flange segment 52 and is spaced from bottom disc face 12b forming an annular groove 54 therewith. The ends 55 and 56 of flange segment 52 form shoulders. End shoulder 55 may engage offset body shoulder 49 when end closure 8 is in closed position (FIG. 1).

An annular segmental recess 57 is formed in the bottom face 12b, of disc 12 and extends circumferentially of end closure 8 from flange segment shoulder 55 a distance, approximately equal to the length of arcuate section 44 (FIGS. 8 and 11).

When end closure 8 is in closed position, the outwardly projecting body flange 50 is slidably engaged in end closure groove 54 and locks end closure 8 against movement axially away from carrier body 2.

Arcuate section 44 seats in recess 57 when end closure 8 is in closed position to provide a stop for end closure 8 and to provide a smooth, uninterrupted surface between end closure 8 and end portion 6 (FIG. 1).

The sudden stopping and starting of the carrier at tube terminals may cause considerable axial force on the end closure as well as the force exerted by the carrier contents following such stops and starts. A person using the carrier for a banking transaction who is unfamiliar with the carrier may attempt to lift the end closure to gain access to the carrier interior instead of pivotally moving the end closure across the carrier open end. Such axial forces could cause damage to the pivotal mounting of the end closure 8 on the carrier body 2. The engagement of carrier-body flange 50 in end closure groove 54 avoids such damage, and also avoids loss of carrier contents from axial separation of closure 8 from the carrier body which is prevented by the flange-groove 50-54 engagement.

End closure 8 in open position is prevented from further counterclockwise movement (FIG. 3) by engagement of disc 12 with shoulder 48 of flange section 44 (FIG. 10). Shoulder 48 stops end closure 8 from reducing the area of open end 7 and prevents rod collar 41 and spring 34 from engaging and binding lug 26.

When held in open position by flange shoulder 48, the overlapping portion of end closure 8 coincides with thickened wall portion 21 thereby providing a maximum access opening area into carrier body 2.

The improved carrier end closure has many advantages. The tapering of side wall 17 of end cap 13 without tapering the ends of carrier body 2 enables carrier 1 to maintain its maximum storage volume while permitting carrier 1 to pass through pneumatic tube bends having smaller radii than heretofore possible. Since carrier

body end sections

44 and 45 are not tapered inwardly as in prior carrier constructions, the large carrier diameter between cylindrical side wall portions 3,

indicated by ,dot-dash diameter line 58 (FIG. 3) is not decreased, thereby permitting articles having a dimension equal to diameter 58 to be placed into carrier body 2 through open end 7.

The end section shoulders 48 and 49 serve as stops for end closure 8 when it is in open and closed positions. Likewise, section 44 extends into recess 57 when closure 8 is in closed position forming an additional stop for closure 8 and also forming a smooth surface free of projections which could retard movement of carrier 1 through the pneumatic tubes.

Flat side wall portions 4 provide a reduced outside carrier body diameter intermediate end portions 6 for conveniently handling the carrier, especially by women or persons who have small hands. Another advantage is the formation of and interengagement of carrier body flange 50 and end closure groove 54 to prevent axial movement between end closure 8 and carrier body 2 when closed.

The construction of end closure 8 of lightweight plastic components eliminates prior metal plates and minimizes problems of premature opening of the end closure due to centrifugal force acting on closure 8 during movement through the pneumatic tube system or inertia upon sudden stopping of the carrier.

The operation of an end closure formed of plastic which is pivotally mounted on a plastic carrier body is greatly facilitated by the particular means by which closure 8 is mounted on the carrier body including the metal bushing 33 between two plastic members to eliminate the pivotal'movement of plastic on plastic.

The improved construction of the invention using spring-biased, end cap, toggle-control means is very simple, sturdy, and shock and fatigue-resistant. The improved construction enables the carrier ends to be tapered so that the carrier can pass through pneumatic tube bends having smaller radii without reducing the diameter of the carrier open end, and without reducing the storage volume of the carrier. The end closure means of the improved construction is formed of lightweight plastic components and is provided with flanges which engage the carrier body for properly positioning the end closure in open and closed position and which provides an effective connection between end closure and carrier body. Furthermore, the improved construction is simple and convenient to load, unload, and dispatch in a pneumatic tube and provides a structure eliminating difficulties that have been encountered in the art, achieving the stated objectives and solving existing problems.

In the foregoing description, certain terms have been used for brevity, cleamess, and understanding; but no unnecessary limitations are to be implied therefrom beyond the requirements of the prior art, because such terms are used for descriptive purposes and are intended to be broadly construed.

Moreover, the description and illustration of the invention is by way of example, and the scope of the invention is not limited to the exact details shown or described.

Having now described the features, discoveries, and principles of the invention, the manner in which the improved carrier end closure construction is built and used, the characteristics of the new construction, and the advantageous, new and useful results obtained; the new and useful structures, devices, elements, arrangements, parts, and combinations are set forth in the appended claims.

We claim:

I. Closure construction for a pneumatic tube carrier including a generally tubular carrier body wall having two ends, at least one of which ends is open and has a cylindrical shape larger than that of the intermediate tubular body wall portion; end closure means for said one open end, and means pivotally mounting the closure means on the body for lateral movement of the closure means across said one open end between fully opened and fully closed positions; the pivotal mounting means including a pivot shaft fixed to the body within the circumference of the larger open end and having an axis, and means journaling the end closure means on said pivot shaft; the end closure means including an end cap and a disc member, the disc member having cavity and bottom faces; the end cap having top and side walls forming a cavity into which an end of the pivot shaft extends; the end cap side walls being smooth, and tapered downwardly and outwardly from the top wall; means securing the disc member to the end cap to close the end cap cavity, the secured disc and the end cap side wall providing the end closure means with a smooth outer side wall free of radially extending projections; spring-biased, toggle-control means located in said end closure cavity for urging the closure means towards and holding said closure means in either fully open or fully closed position; the larger cylindrical one open end of the carrier body terminating in first and second connected curved sections, with said first curved section having a shorter length than the second curved section; the first section being arcuate and having a radius of curvature equal to the radius of the carrier body cylindrical open end and projecting axially beyond the end of the second section; the first end section terminating in first and second shoulder means; said first shoulder means engaging the end closure means to stop said end closure means upon reaching open position; the second section having a first arcuate portion with a radius of curvature equal to the radius of said first curved section, and a second portion extending in chord-like fashion between said first curved section and the arcuate portion of the second curved section; the first end section first shoulder means being arcuately aligned with the arcuate portion of the second end section, and the second shoulder means being offset laterally outwardly of the chord-like second portion of said second end section; curved flange means formed on the chord-like portion and projecting laterally outwardly therefrom and terminating within the periphery of the cylindrical open end; the end closure means having an arcuate flange segment having a radius of curvature equal to the radius of the cylindrical open end and extending axially below the bottom face of the disc member; a laterally inwardly projecting flange at the free end of said flange segment spaced from the bottom face of the disc member and forming groove means with said disc member; the closure means having an annular segmental recess formed therein and extending above the bottom face of the disc member and circumferentially of the closure means; and said annular segmental end closure recess extending a distance generally equal to the arcuate length of the projecting first end section, whereby the outwardly projecting body flange means is seated in the end closure groove means when the closure means is in closed position, and said end closure segmental recess receiving and overlying the projecting first body section when the closure means is in closed position.

2. The construction defined in claim 1 in which the second shoulder engages the end closure means flange segment to stop said end closure means upon reaching closed position.

3. The construction defined in claim 1 in which the ends of the end closure flange segment are provided with shoulders; and in which one of said shoulders is engageable with the offset body shoulder when the closure means is in closed position.

4. The .construction defined in claim 1 in which the closure means includes a sleeve on the end cap; in which the carrier body wall has an enlarged recess surrounding the pivot shaft; in which a bushing member is with said lug; and in which the spring means includes stop means located within the cavity, a rod pivotally connected at one end with the lug and at the other end with the stop means, and a compression coil spring surrounding said rod reactively engaged with said stop means.

7. The construction defined in claim 6 in which projections are formed on the end cap and disc member cavity face; and in which said projections extend into the end closure cavity forming said stop means.

Claims

1. Closure construction for a pneumatic tube carrier including a generally tubular carrier body wall having two ends, at least one of which ends is open and has a cylindrical shape larger than that of the intermediate tubular body wall portion; end closure means for said one open end, and means pivotally mounting the closure means on the body for lateral movement of the closure means across said one open end between fully opened and fully closed positions; the pivotal mounting means including a pivot shaft fixed to the body within the circumference of the larger open end and having an axis, and means journaling the end closure means on said pivot shaft; the end closure means including an end cap and a disc member, the disc member having cavity and bottom faces; the end cap having top and side walls forming a cavity into which an end of the pivot shaft extends; the end cap side walls being smooth, and tapered downwardly and outwardly from the top wall; means securing the disc member to the end cap to close the end cap cavity, the secured disc and the end cap side wall providing the end closure means with a smooth outer side wall free of radially extending projections; spring-biased, togglecontrol means located in said end closure cavity for urging the closure means towards and holding said closure means in either fully open or fully closed position; the larger cylindrical one open end of the carrier body terminating in first and second connected curved sections, with said first curved section having a shorter length than the second curved section; the first section being arcuate and having a radius of curvature equal to the radius of the carrier body cylindrical open end and projecting axially beyond the end of the second section; the first end section terminating in first and second shoulder means; said first shoulder means engaging the end closure means to stop said end closure means upon reaching open position; the second section having a first arcuate portion with a radius of curvature equal to the radius of said first curved section, and a second portion extending in chord-like fashion between said first curved section and the arcuate portion of the second curved section; the first end section first shoulder means being arcuately aligned with the arcuate portion of the second end section, and the second shoulder means being offset laterally outwardly of the chord-like second portion of said second end section; curved flange means formed on the chord-like portion and projecting laterally outwardly therefrom and terminating within the periphery of the cylindrical open end; the end closure means having an arcuate flange segment having a radius of curvature equal to the radius of the cylindrical open end and extending axially below the bottom face of the disc member; a laterally inwardly projecting flange at the free end of said flange segment spaced from the bottom face of the disc member and forming groove means with said disc member; the closure means having an annular segmental recess formed therein and extending above the bottom face of the disc member and circumferentially of the closure means; and said annular segmental end closure recess extending a distance generally equal to the arcuate length of the projecting first end section, whereby the outwardly projecting body flange means is seated in the end closure groove means when the closure means is in closed position, and said end closure segmental recess receiving and overlying the projecting first body section when the closure means is in closed position.

4. The construction defined in claim 1 in which the closure means includes a sleeve on the end cap; in which the carrier body wall has an enlarged recess surrounding the pivot shaft; in which a bushing member is telescoped within the enlarged recess; and in which the sleeve is journaled on said pivot shaft within said bushing.

5. The construction defined in claim 1 in which both the end cap and the disc member are formed of plastic material.

6. The construction defined in claim 1 in which the control means includes a laterally extending lug rigidly mounted on the pivot shaft end within said cavity, and spring means within said cavity operably connected at one end with the closure means and at the other end with said lug; and in which the spring means includes stop means located within the cavity, a rod pivotally connected at one end with the lug and at the other end with the stop means, and a compression coil spring surrounding said rod reactively engaged with said stop means.