US3720956A - Face shield - Google Patents

Abstract

A detent joint for pivotally securing a face shield holder to a stationary head gear. The joint is constructed of a pair of identical resilient discs secured to the holder and the head gear, respectively, pivotable about a common pin, and firmly held in mutual contact by thrust shoulders of the pin. The discs include a plurality of coacting detents that are equally spaced from each other and from the pivot axis so that upon pivotal movement of the face shield holder the detent and depressions intermittently register and maintain the face shield in a plurality of angularly spaced positions.

Description

[ 1March 20, 1973 [54] FACE SHIELD Herbert A. Raschke, Greenbrae, Calif.

[73] Assignee: E. D. Bullard Company, Sausalito,

Calif.

[22] Filed: May 19, 1971 [21] App]. No.: 146,578

[75] Inventor:

[52] US. Cl ..2/8

51 Int. Cl. ..A42b 1/00 [58] Field of Search ..2/10, 8, 9, 4, 5, 6, 7; 287/ 14, 101

[56] References Cited UNITED STATES PATENTS 2,736,027 2/1956 Parmelee ..2/3 3,067,426 12/1962 Tompkins ..2/8

114,914 l2/l963 Ruggiero ..2/8

Primary Examiner-H. Hampton Hunter Attorney-Townsend & Townsend 5 7 ABSTRACT A detent joint for pivotally securing a face shield holder to a stationary head gear. The joint is constructed of a pair of identical resilient discs secured to the holder and the head gear, respectively, pivotable about a common pin, and firmly held in mutual contact by thrust shoulders of the pin. The discs include a plurality of coacting detents that are equally spaced from each other and from the pivot axis so that upon pivotal movement of the face shield holder the detent and depressions intermittently register and maintain the face shield in a plurality of .angularly spaced positions.

2 Claims, 6 Drawing Figures PATENTEDMARZO I975 3.720.956.

SHEET 1 or 2 M 7O,- INVENTOR.

HERBERT A. ERASCHKE FIG. 2

BY ATTORNEYS PMENIEnmzo m5 3. 720,956

SHEET 2 OF 2 I N VEN'TOR,

HERBERT A. RASCHKE WW/ w z wwz ATTORNEYS FACE sins-Ln BACKGROUND OF THE INVENTION A relatively large number of face shields are used to protect workmen, law enforcement personnel and the like. For optimum utility, the face shields are so mounted that they can be pivoted between a face pro tecting or covering position and a position in which the face of the wearer is open and uncovered. A variety of devices are known for maintaining the face shield in the two terminal positions.

Such face shield positioning and holding devices usually employ snap-in means in which two members secured to the shield and to a portion of a stationary head gear are mounted for axial movement so that de tents, grooves and the like on the members can move into and out of mutual registration. The axial movement of the members is obtained from resilient mounts such as soft rubber sleeves, springs, and the like for the members. By necessity, such mounts substantially protrude past the sides of the face shield and the head gear and are thus a potential hazard since they can accidentally engage structures and the like and move the face mask or pull it completely off the wearers head.

In addition, known prior art face mask positioning devices are relatively complicated, expensive and susceptible to premature wear particularly where components of the resilient mounts are constructed of relatively readily deteriorable materials such as rubber. The relative bulkiness of prior art devices usually limited the positioning and retention of the face shield to two, 90 offset face covering and uncovering positions. No provisions were made for positioning and retaining the face shield at intermediate points to permit the wearer, for example, to touch his face, clean his eyes and the like without completely losing the protection afforded by the face shield.

SUMMARY OF THE INVENTION The present invention provides a pivotal detent joint for face shields and the like which is rugged, simple to construct and which readily permits the positioning and retention of the face shield at points intermediate the face covering and uncovering positions of the shield. Generally speaking, the present invention provides an apparatus for connecting a first part, e.g., a face shield holder, to a second part, e.g., a head gear, for relative pivotal movements of the parts about a pivot axis. The apparatus comprises a first resilient disc attached to the first part and having a hole concentric with the pivot axis. A second resilient disc is attached to the second part and also has a hole concentric with the pivot axis. A pin extends through the holes concentric with the axis and includes thrust shoulders on opposite ends thereof for retaining the discs in intimate face-to-face contact. Each disc has at least first and second detents that are equally radially spaced from the axis and face in like directions for intermittent mutual engagement of the detents and the positioning and retention of the members at spaced apart points.

The discs are substantially identical and are directly secured, e.g., riveted to the face shield holder and the head gear for intimate face-to-face contact without permitting axial movements of the discs. This reduces manufacturing costs and prevents protruding components which may represent a safety hazard. Relative movements of the detents in the two discs in an axial direction. as they move into and out of registration is I obtained from the resiliency of the discs. It is preferred that sufficient spaced apart detents are provided in the discs so that the face shield holder can be positioned and retained at points intermediate the substantially vertical face protecting or covering position and a face uncovering, generally horizontal position. This permits the wearer to quickly pivot the face mask upwardly to catch a breeze of fresh air, clean or dry his face, etc. without fully loosing the protection of the shield and to thereafter quickly pull the shield downwardly into its fully protecting position.

The elimination of relatively complicated mounts permitting axial movements of the positioning members found in prior art devices eliminates the need for easily worn out or damaged parts such as rubber discs, springs and the like and further permits the exertion of a substantial axial force for biasing the discs into faceto-face contact. The relatively large force enables the construction of the disc with relatively small, generally spherical detents having a diameter of as little as about 1/16 of an inch without compromising the holding power of the joint. The small detent size permits the inclusion of substantial numbers of detents, e.g., eight or more per disc which further increases the pivot joints holding power while it simultaneously increases the numberof angularly spaced positions in which the face shield can be retained.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevational view of a conventional hard hat to which a face shield is mounted with a pivotal detent joint constructed in accordance with the invention;

FIG. 2 is a top view of the hat, face shield and detent joints shown in FIG. 1;

FIG. 3 is an enlarged, fragmentary view, partially in section, of a preferred installation of the detent joints and is taken on line 3-3 of FIG. ll;

FIG. 4 is an enlarged, fragmentary view, partially'in section, similar to FIG. 3 but shows another manner of installing the detent joint shown in FIG. 1

FIG. 5 is an enlarged, cross sectional side elevation of the detent joint and is taken on line 5--5 of FIG. 1;

and

FIG. 6 is an enlarged, exploded view of the detent discs of the joint illustrated in FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIGS. 1 and 2, a face shield 10 is shown mounted to a shield holder 12 and is pivotally movably secured to a mounting rail 14 with a pair of aligned detent joints 16 constructed in accordance with the invention. In the illustrated embodiment the mounting rail is generally horseshoe shaped, has a U-shaped cross section and fits over a rim 18 of a hard hat or helmet 20. Free ends of the rail include apertures 22 engaged by ends 24 of a helical tension spring 26 that is wrapped aboutan aft portion 28 of the helmet and firmly retains the mounting rail to the helmet rim.

In use, the wearer places the helmet over his head and lowers face shield 10 into a substantially vertical position (shown in FIG. 1 in solid lines) in which the shield covers and protects his face. The shield can be pivoted upwardly in a counterclockwise direction, as viewed in FIG. 1, into a face uncovering, generally horizontal or inclined position (shown in phantom lines in FIG. 1) in which the wearer's face is free of and unprotected by the shield.

Referring to FIGS. 1 through 3, 5 and 6, each detent joint 16 comprises a pair of identical discs 30 each of which includes an arm 32 that extends radially away from the disc. Each disc includes a concentric bore 34 at a center portion of the disc that defines a pivot axis 36 of the joint and a plurality such as eight equally spaced detents 38 that lie on a common circle concentric with the pivot axis in a peripheral portion of the disc.

The discs are constructed of relatively thin, resilient material such as steel. Each detent thus defines a depression 40 on one side of the disc and a corresponding protrusion 42 at the other side of the disc. A rivet 44 extends through disc bores 34 and an aligned bore 46 in mounting rail 14 for securing the discs to the rail and firmly biasing opposing faces 48 of the discs into firm contact.

Each disc arm 32 has a pair of apertures 50. A first disc is riveted to the rail by the aforementioned rivet 44 and a second rivet 52 extending through aperture 50 in arm 32 proximate the disc. This rigidly secures the disc to the rail. The second aperture 50 of that disc remains open and is aligned with aperture 22 in the rail through which spring end 24 extends as is shown in FIG. 3. Arm 32 of the other disc is mounted to end 54 of shield holder 12 by a pair of rivets 56 extending through disc arm apertures 50 and aligned holes 58 in the shield holder.

A pair of detent joints 16 is provided for each face shield and they are located at opposite sides of the helmet in axial alignment as best seen in FIG. 2. The biasing force exerted by rivet 44 firmly presses opposing disc faces 48 into engagement. When detents 38 of each disc pair are angularly aligned and face in the same direction, the protrusions 42 on one of the discs register with the depressions 40 on the other disc. This registration of the depression and protrusion places the discs and therewith shield holder 12 and mounting rail 14 in predetermined relative angular positions and retains them in such position until a sufficient force is applied to the discs (via the holder and the rail) to resiliently deflect the peripheral portion of the discs in an axial direction (of pivot axis 36) with respect to the disc center to move the protrusions and depressions out of registration. The discs are then free to pivot about pivot axis 36 through an are (45 when eight equally spaced detents are employed) until the depressions and protrusions are again in registration.

Referring to FIG. 3, in a preferred embodiment of the invention, disc 30 mounted to rail 14 is installed so that protrusions 42 face the rail. This deforms both discs outwardly, as shown in FIG. 3, pretensions the discs and results in a greater biasing force between opposing disc faces 48. This in turn increases the holding force of the joint when the detents are in registration so that for a desired holding force for the face shield relatively small detents are sufficient. When employing conventional C-l035 tempered spring steel of a thickness of 0.020 inches detent diameters between about 1/16 to 3/32 of an Il'lCh and protrusion heights of between about 1/32 and 1/16 of an inch are sufficient to securely retain the face shield inposition and prevent unintended pivotal movements of the shield.

Referring briefly to FIG. 4, entirely satisfactory results are also obtained with the detent joint of the present invention when disc 30 secured to mounting rail 14 is positioned so that its detents 38 face away from the rail. When so installed the discs remain flat and undeformed, as compared to the preferred installation illustrated in FIG. 3, and the force with which opposing disc faces 48 are biased against each other depends solely on the pretensioning of rivet 44. In use, such an installation results in slightly lesser forces between the opposing disc faces. For use of the joint with relatively heavy face masks the diameter of detents 38 and/or the heights of protrusions 42 may have to be increased slightly to obtain the desired holding force.

I claim:

1. A face shield for a head gear permitting pivotal movement of the shield for covering and uncovering the wearer's face, the shield comprising: a first rail for engagement with the head gear, means for retaining the rail to the head gear, a pivot member rigidly secured to the rail and including a thin, flexible disc, a shield holder, a second member substantially identical to the first mentioned member rigidly secured to the holder and including another thin, flexible, disc, a pin extending through the discs, means securing the discs to each other, and permitting relative pivotal movements of the discs about the pin and preventing relative axial movement of the discs, the discs including a plurality of detents facing in like directions and equally radially spaced from the pin axis for intermittent mutual engagement of the detents during relative pivotal movements of the discs and the rail and holder to index the rail and the holder at predetermined positions so that the face shield may be raised from over and lowered over the wearers face and retained in predetermined positions.

2. A face shield according to claim 1 including a sufficient number of detents which are spaced to permit the positioning of the face shield at points intermediate an essentially vertical, face covering position and an inclined or generally horizontal, face uncovering position.

l 4 l t

Claims (2)

1. A facE shield for a head gear permitting pivotal movement of the shield for covering and uncovering the wearer''s face, the shield comprising: a first rail for engagement with the head gear, means for retaining the rail to the head gear, a pivot member rigidly secured to the rail and including a thin, flexible disc, a shield holder, a second member substantially identical to the first mentioned member rigidly secured to the holder and including another thin, flexible, disc, a pin extending through the discs, means securing the discs to each other, and permitting relative pivotal movements of the discs about the pin and preventing relative axial movement of the discs, the discs including a plurality of detents facing in like directions and equally radially spaced from the pin axis for intermittent mutual engagement of the detents during relative pivotal movements of the discs and the rail and holder to index the rail and the holder at predetermined positions so that the face shield may be raised from over and lowered over the wearer''s face and retained in predetermined positions.

2. A face shield according to claim 1 including a sufficient number of detents which are spaced to permit the positioning of the face shield at points intermediate an essentially vertical, face covering position and an inclined or generally horizontal, face uncovering position.

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