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Publication numberUS3413972 A
Publication typeGrant
Publication dateDec 3, 1968
Filing dateSep 27, 1965
Priority dateSep 27, 1965
Publication numberUS 3413972 A, US 3413972A, US-A-3413972, US3413972 A, US3413972A
InventorsDepping Carl L
Original AssigneeCarl L. Depping
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Airflow helmet
US 3413972 A
Abstract  available in
Images(2)
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Claims  available in
Description  (OCR text may contain errors)

Dec. 3, 1968 c. L. DEPPING 3,413,972

I AIRFLOW HELMET Filed Sept. 27, 1965 2 Sheets-Sheet l Carl L. Depping INVENTOR.

Dec. 3, 1968 c, DEPP|NG I 3,413,972

AIRFLOW HELMET Filed Sept. 27, 1965 2 Sheets-Sheet 2 Cbr/ L. flapping I N VEN TOR.

T a M k //3 1/0 06 W United States Patent 3,413,972 AIRFLOW HELMET Carl L. Depping, Walla Walla, Wash. (R.F.D. 3, Armstrong, British Columbia, Canada) Filed Sept. 27, 1965, Ser. No. 490,319 6 Claims. (Cl. 128142.7)

ABSTRACT OF THE DISCLOSURE A helmet completely enclosing the head of a wearer with spaced concentric shells defining an air passage therebetween, an air blower discharges air into the air passage adjacent the rear thereof and an outlet is provided adjacent the bottom front of the helmet to circulate air therethrough. The inner shell terminates above eye level and is supported from the head in spaced relation to provide air circulation between the inner shell and the head of the wearer. The inner shell is provided with openings communicating with the air passage so that air passing through the air passage will entrain air from interiorly of the inner shell to circulate air about the head of the wearer. The air passing through the air passageway is prevented from passing rearwardly beyond the face area of the wearer by a seal structure and the air also passes over the interior of a transparent panel forming a portion of the outer shell.

The present invention relates generally to protective devices and more specifically to devices of the type which supply fresh, filtered air to persons working under extreme conditions of dust and other debris in the atmosphere.

A recognized hazard to health encountered in various industries, including the operation of farm devices, such as harvesters or cultivators, is the possibility that dust and debris which is present in the atmosphere will be inhaled by persons involved in such work. In the past, various protective devices have been devised to obviate this health hazard. However, these prior devices have proved generally unsatisfactory in that they unduly restricted the users range of travel and proved generally unsatisfactory to fully protect the user from wind-blown dust and debris. Fur ther, these prior devices also ordinarily do not allow the user full freedom of head movement and require removal to allow the user to communicate. Further, these prior devices do not provide adequate ventilation for the user, thereby making the user uncomfortable and lessening his efiiciency.

Accordingly, it is an object of the present inventon to provide a ventilated protective covering device for protecting persons operating in dust-laden atmospheres from inhalation of dust.

It is another object of the present invention to provide a helmet device for placement over a users head which includes a filter and blower for use therewith, the filter and blower adapted to be carried by the user or mounted on an implement being operated by the user.

It is another object of the present invention to provide a ventilated helmet having a novel face plate and ventilator means for use therewith.

It is a still further object of the present invention to provide a helment adapted for placement on the wearers head and used in conjunction with a collar supported by a shoulder rest to protect the user from dust and debris in the atmosphere.

It is another object of the present invention to provide a ventilated helmet which may be fabricated out of readily available materials and which is lightweight while at the same time being quite sturdy in construction.

These together with other objects and advantages which will become subsequently apparent reside in the details ice of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout, and in which:

FIGURE 1 is a front elevational view of the protective device comprising the present invention.

FIGURE 2 is a side elevational view corresponding to FIGURE 1.

FIGURE 3 is a rear elevational view corresponding to FIGURES 1 and 2.

FIGURE 4 is an enlarged vertical sectional view taken substantially along the plane of the line 4-4 of FIG- URE 1.

FIGURE 5 is a top plan view corresponding to the view of FIGURE 4 partially broken away to illustrate the interior of the helmet.

Referring now to the drawings and specifically to FIG- URES 1-3, reference numeral 10 refers generally to the ventilator device of the present invention. The ventilator device 10 includes a helmet portion 12, a collar portion 14 and a shoulder rest portion 16. The shoulder rest portion 16 is preferably constructed of a heavy-duty material such as canvas or the like and includes a collar portion 18 which is adapted to fit snugly about the wearers neck with a soft lining. The shoulder portion 16 includes a Zipper 20 of conventional design which enables the wearer to retain the shoulder rest in place, the Zipper 20 being positioned in the front portion of the shoulder rest and extending upwardly through the collar portion 18. Thus it may be observed in FIGURES 1-3 that the shoulder rest 16 fits snugly on the wearers shoulders and around the wearers neck when in place. The shoulder rest 16 is retained in place on the wearer by adjustable straps 22 and 24 which fit through the openings 26 and 28 in the front portion of the shoulder rest at one end. The straps 22 and 24 are adapted to fasten under the wearers arms in order to make the shoulder rest fit snugly on the wearers shoulders and are fastened at their other ends at 30 and 32 to openings 42 and 44 at the back of shoulder rest 16. Straps for a mounting board 40 include a separate set of harness straps to be described more fully below.

The collar 14 is preferably fashioned from a heavy-duty material such as described above. This collar 14 includes a conventional heavy-duty Zipper 34 extending vertically along the front portion thereof, thus enabling the collar 14 to be placed about the wearers neck and under the wearers chin and retained thereon. The collar 14 includes a half-zipper portion 36 which is adapted to mate with the other half-Zipper portion which is positioned on the extreme bottom portion of the helmet 12, thereby providing a means for attaching the helmet 12 to the collar 14. Thus by viewing FIGURES 1-3 it may be observed that the collar portion 14 is mounted about the wearers neck and under the wearers chin over the collar portion 18 of shoulder rest 16 by fastening the zipper 34, and then the helmet 12 is attached to the upper portion of the collar 14 by zipper 36. It will be appreciated that by the combination of the shoulder rest 16, the collar 14 and the helmet 12, there is provided a complete covering for the wearers head, neck and upper shoulders. As the collar portion 18 of the shoulder rest 16 fits tightly about: the wearers neck and the collar 14 fits over the collar portion 18, any dust or debris which is blown or carried by the wind will be unable to enter into the helmet 12 and thus the wearer is fully protected from such dust or debris.

The mounting board 40, mentioned above, is preferably composed of wood, plastic or other suitable materials and includes the openings 39, 41, 43 and 45 in each of the four outside corner portions thereof in which adjustable straps 47 and 49 are fastened in similar fashion to a conventional pack-board harness. Adjustable straps 47 and 49 fasten over the users shoulders and under his arms to hold board 40 firm while at the same time allowing the board 40 to be put on and worn separately from the shoulder rest 16. An adjusting buckle 51 in front draws the straps 47 and 49 together to hold the mounting board 40 tightly against the wearers back. Mounted on the mounting board 40 by a conventional mounting means is the motor 46, which is preferably a small AC motor which is commonly used in a fan or the like. The motor 46 is used in conjuction with a blower 48 of conventional design, in this instance and being illustrated as a rotary fan or blower having an inlet 52 and an exhaust 56. The motor and blower are mounted in the housing 50 which housing is attached to the mounting board 40 by conventional mounting means. The inlet of the blower 48 has an air filter 54 mounted thereover, thereby filtering the air which is drawn into the blower. The exhaust opening 56 of the blower 48 has a flexible hose 58 attached thereto, which hose extends through the side wall of the housing 50 and is attached to the helmet 12 as at 60. Thus, in view of the foregoing, it will be apparent that the motor and blower arrangement when used in conjunction with the air filter 54 will supply fresh filtered air to the helmet. Operating current is supplied to the motor 46 by the electrical leads generally designated by numeral 62. The motor 46 is preferably a two-speed motor and the control switch 64 for switching the motor to its high and low operating positions is fastened on the shoulder strap 49. The control switch 64 is connected to the motor by electrical lead 66, which lead is connected to the strap 49 as at 68 and the switch 64 is mounted to allow the operator to easily control the motor speed and thus vary the amount of filtered air delivered to the helmet merely by reaching up and operating the switch 64. The switch 64 is of conventional electrical design and forms no part of the present invention.

The helmet 12 is preferably constructed from a plastic material or the like, which is substantially sturdy while at the same time being lightweight. The helmet 12 includes a face plate 70 which is hingedly mounted on the helmet as at 72, an air discharge port 74 and an air inlet port portion 76.

Referring now to FIGURES 4 and for a more detailed description of the helmet 12, it will be observed that the helmet 12 when in place on the wearers head and held thereon by zipper 36 is maintained in spaced relation to the wearers head by the suspension band generally designated by reference numeral 78. The suspension band preferably consists of a first portion 80 which extends about the wearers head and a second portion 82 which extends over the top of the wearers head being joined at its ends to the first portion 80. The suspension band 78 is releasably held in the helmet 12, for example by snap fasteners 84 and 86. Thus, the band 78 may be removed to be cleaned or replaced. The suspension band is attached to the inside of the helmet by the aforementioned snap fasteners and is adjustable therein by adjustment means (not shown) so that the helmet can be adapted to fit on the heads of various wearers. A cushion member 88 is provided in the helmet 12 and includes substantially parallel side portions 90 and 92 as well as a front chin portion 94. The cushion 88 is attached to the inner side walls of the helmet as for example by straps or clips therein and extends inwardly from the side walls so that a wearer when positioning the helmet on his head compresses the cushion 88 against the side of his face thus holding the helmet 12 tightly in place on the wearers head and effectively dividing the interior of the helmet 12 into a first chamber 90 and a second chamber 92. It will be apparent by viewing FIGURE 4, that due to the suspension band 78 and the cushion -88 mounting the helmet 12 tightly on the wearers head, the wearer may move his head from side-to-side and in doing so will not cause relative movement between his head and the helmet. Rather, the helmet 12 will readily move with the operators head due to the aforementioned tight fit as well as the slidable mounting relationship between the collar 14 and the collar portion 18.

The face plate 70 is preferably constructed of transparent plastic or Plexiglas in order to be lightweight and yet strong. The pivotal connections 72, one on each side of the helmet 12, allow the face plate 70 to be moved forward and upwardly, thereby uncovering the frontwardly opening port 96 and allowing the wearer to communicate without removing the helmet 12 from his head. The pivotal connection 72 includes identical arms 98 and 100 which are pivotally connected at one end to the helmet 12 by pins 102 and 104 that extend through the helmet to the inside thereof. A pair of identical arms 105 (only one of which is illustrated) are connected to the other ends of pins 102 and 104 and extend parallel to arms 98 and 100. The face plate 70 is pivotally connected to arms 98 and 100 by extensions 106 and 108 and mounting pins 110 and 112. A pair of tension springs 118 and are mounted on pins 110 and 112 to provide constant adjustment for arms 106 and 108. A pair of identical wing nuts 113 are provided on pins 110 and 112 to adjust the tension on arms 106 and 108 to help hold face plate 70 in up position. Attached to arms 105 are coil springs 114, which are attached at one end to the inside wall of the helmet as indicated at 118. Thus, it may be observed that the face plate 70 can be pulled away from the port or opening 96 of the helmet 12 by a forward pull thereon thereby pivoting the arms 98 and 100 about pins 102 and 104. The face plate 70 then may be swung upwardly to the position shown in FIGURE 4. The opening or port 96 includes a seal member 122 positioned about the periphery thereof. Thus, when the face plate 70 is in place over the port 96 the springs 114 and 116 apply inward pressure on the face plate 70 thereby causing the face plate to be sealingly engaged over the port 96.

The connection 60 of flexible hose 58 to the helmet 12 is best illustrated in FIGURE 4 wherein it is shown that the flexible hose 58 fits in a rearwardly extending appendage portion 124 of helmet 12. This appendage portion 124 includes the air inlet port 76 therein which inlet port is generally circular and adapted to receive the hose 58 therein. The connection between hose 58 and air inlet port 76 is illustrated as a frictional fit and the hose 58 is held therein by depressable wings 79 and 81. However, it would be possible to provide a conventional threaded fit. The appendage portion 124 forms the first portion of a conduit or channel 126 which has as its upper wall the top 128 of the helmet 12. The bottom of the conduit or channel 126 comprises a bottom wall 130 which is spaced from the top wall 128 a substantially equal distance throughout its surface area.

The bottom wall 130 includes a plurality of ventilating ports or louvers 132 therein, which ports serve to communicate the second chamber 92 of the helmet with the channel or conduit 126. The conduit 126 is completed by side walls 134 and 136 which extend between the bottom wall 130 and the top wall 128. Referring to FIGURE 5 it may b eseen that the conduit 126 is relatively narrow at the rear end of the helmet adjacent the air inlet port 76 and widens out at the front portion of the helmet at which point it communicates with the front chamber 90 by elongaated opening 138. Thus, it may be observed that filtered air is forced through the pipe 58, through the air inlet port 76 and into the channel or conduit 126. As this air flows through the channel or conduit 126 hot or stale air which is contained in the rear chamber 92 is drawn upwardly through the openings 132 in bottom wall 130 and flows along the conduit 126 through opening 138 into the front chamber 90. The air discharge port 74 which is positioned in the bottom and front of the helmet 12 is in communication with the front chamber 90. Thereby air which is forced into the front chamber 90 will be expelled out through air discharge port 74 as the air cannot flow rearwardly into the chamber 92 of the helmet due to the blocking action of the cushion 88. The air flowing into the front chamber 90 will flow across the inside of the face plate 70 and will keep the face plate free from condensation which otherwise would normally form thereon. This air flow further provides the operator with fresh filtered air and prevents dust from entering the air discharge port 74. The air discharge port 74 also is covered with a screen member 140 to further operate to keep out the dust.

Referring to FIGURE 4, it will be observed that the helmet contains enough room to position a short-wave radio set, designated at 144, adjacent the users ear. In further reference to this figure, it may be observed that the flow of air through the helmet is indicated by the various arrows thereon.

This helmet has been tested under various Weather and dust conditions and, due to its particular construction and placement of the ventilating means as well as its combination with the collar 14 and shoulder rest 16 allows the wearer to operate efiiciently under extreme conditions. This helmet design provides fresh air at all times, eliminates condensation on the side of the face plate and prevents dust and debris from entering and disturbing the wearer.

It will be readily apparent that this helmet 12, collar 14 and shoulder rest 16 may be used in conjunction with the blower mounted on the wearers back for a self-sufficient unit by use of mounting plate 40. Also, the mounting plate 40 may be dispensed with and the helmet and shoulder rest used with compressed air tanks mounted in the vicinity of the wearers working station, as on a tractor, combine or the like, the helmet being connected to the compressed air tank or an air filter unit by a flexible hose similar to hose 58 as the operator sits on the vehicle seat.

The foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly all suitable modifications and equivalents may be resorted to, falling within the scope of the invention as claimed.

What is claimed as new is as follows:

1. In combination with a helmet having an outer shell with an air inlet adjacent the rear thereof for receiving pressurized air and a front outlet adjacent the bottom thereof; that improvement comprising, an inner member attached to the inner surface of the shell to define an air passageway, said inner member having a front edge terminating above the eye level of a wearer so that air will be discharged downwardly between the face of the wearer and the shell, headband means mounted in the helmet to maintain the head of the wearer in spaced relation to said inner member, openings in said inner member communicating the air passageway with the interior of the helmet, and face seal means mounted in the helmet for establishing a thermal circulation of hot air from the helmet interior to the air passageway.

2. The helmet structure set forth in claim 1 wherein the rear portion of the inner member is relatively narrow and the forward portion of the inner member flares laterally outwardly to define a horizontally disposed air pasageway portion for passage of air downwardly in front of the face of the wearer.

3. The helmet structure defined in claim 1 together with a shoulder engaging supporting structure attached to said helmet, harness means securing the shoulder engaging structure in position thereon, a blower for inducing flow of air, a flexible hose communicating the blower with the air passageway, and a back mounting board supporting said blower, said back mounting board including harness means for supporting the mounting board along the surface of the back of the wearer.

4. The helmet apparatus set forth in claim 1 wherein said outer shell includes a transparent face plate pivotally mounted for enabling access to the face of the wearer, and seal means sealing said transparent face plate to said helmet.

5. A helmet adapted to substantially completely enclose the head of a wearer comprising an outer shell and an inner shell spaced from each other to define an air passage, the rear portion of the inner shell being relatively narrow and connected with the outer shell to define an air conduit, means supplying air to the rear bottom portion of the air conduit, the forward portion of the inner shell flaring laterally outwardly to define a horizontally disposed air passageway for passage of air downwardly in front of the face of the wearer, said outer shell having an air outlet adjacent the lower edge of the front portion thereof, and means connected with the outer shell and forming a closure for the side portions of the inner shell and adapted to engage the surfaces of the face of the wearer along each side thereof for directing air out through the outlet, said inner shell including a harness to engage the head of the wearer to space the head of the wearer from the interior surface of the inner shell thereby providing an air space therebetween, said inner shell including openings therein communicating with the air passage so that air passing along the air passage will entrain air through the openings in the inner shell thereby circulating air in relation to the head of the wearer, shoulder engaging supporting structure attached to said helmet, harness means securing the shoulder engaging means in position thereon, a blower for inducing flow of air, a flexible hose communicating the blower with the air conduit, and a back mounting board supporting said blower, said back mounting board including harness means for supporting the mounting board along the surface of the back of the wearer.

6. The structure as defined in claim 5 wherein said outer shell includes a transparent face plate pivotally mounted thereon for enabling access to the face of the wearer, said means connected with the outer shell engaging the side surfaces of the face of the wearer including a strip of soft resilient material secured to the inner surface of the outer shell.

References Cited UNITED STATES PATENTS 1,000,721 8/1911 Cypra 128-142.7 X R 1,410,926 3/1922 Knoblock 128-142.7 2,688,962 9/1954 Summers 128142.3 2,861,568 11/1958 Quilter et al 128-1423 3,078,845 2/1963 Kohlmeyer 128- 142.7 3,223,086 12/ 1965 Denton 128-142 3,258,010 6/1966 Austin et al 128142.7 3,293,659 12/1966 Shepard 12S--142.7 XR 3,310,811 3/1967 Iacono 22.1 XR

RICHARD A. GAUDET, Primary Examiner. K. L. HOWELL, Assistant Examiner.

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Referenced by
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USD779128May 20, 2016Feb 14, 2017Illinois Tool Works Inc.Protective helmet
USD781502May 20, 2016Mar 14, 2017Illinois Tool Works Inc.Protective helmet
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Classifications
U.S. Classification128/201.23
International ClassificationA62B18/00, A62B18/04
Cooperative ClassificationA62B18/045
European ClassificationA62B18/04A