The present invention generally relates to lighters such as pocket lighters used to light cigarettes and cigars, or utility lighters used to ignite candles, barbecue grills, fireplaces and campfires, and more particularly to such lighters which resist inadvertent operation or undesirable operation by unintended users.
Lighters used for igniting tobacco products, such as cigars, cigarettes, and pipes, have developed over a number of years. Typically, these lighters use either a rotary friction element or a piezoelectric element to generate a spark near a nozzle which emits fuel from a fuel container. Piezoelectric mechanisms have gained universal acceptance because they are simple to use. U.S. Pat. No. 5,262,697 to Meury discloses one such piezoelectric mechanism, and the disclosure in the '697 patent is incorporated by reference herein in its entirety.
Lighters have also evolved from small cigarette or pocket lighters to several forms of extended or utility lighters. These utility lighters are more useful for general purposes, such as lighting candles, barbecue grills, fireplaces and campfires. Earlier attempts at such designs relied simply on extended actuating handles to house a typical pocket lighter at the end. U.S. Pat. Nos. 4,259,059 and 4,462,791 contain examples of this concept.
Many pocket and utility lighters have had some mechanism for resisting undesired operation of the lighter by young children. Often, these mechanisms are on/off switches which may shut off the fuel source or may prevent movement of an actuator, such as a push-button, on the lighter. On/off switches which a user positively moves between “on” and “off” positions can be problematic. For example, an adult user may forget to move the switch back to the “off” position after use and thereby render the feature ineffective.
Other pocket and utility lighters include a spring-biased blocking latch which arrests or prevents movement of the actuator or push-button. U.S. Pat. No. 5,697,775 to Saito and U.S. Pat. No. 5,145,358 to Shike, et al., disclose examples of such lighters.
There remains a need for lighters which resist inadvertent operation or undesirable operation by unintended users, that is easy to manufacture, has a minimal number of components and that is consumer-friendly for the intended user, and it is the focus of the present invention to meet this need.
In accordance with the present invention, the foregoing needs and object have been met. According to the invention, a lighter design is provided which reduces the number of components required to make the lighter child resistant to the quantity that was used in lighters prior to increasing the efforts to improve the child resistancy of lighters. This lighter design significantly reduces cost and complexity while providing a lighter which is both child resistant and user friendly to those who are adults, and thereby, intended users.
The present invention relates to a lighter, such as a pocket lighter or a utility lighter. a housing having a supply of fuel; an ignition mechanism for igniting fuel from the supply of fuel; an activating unit movably associated with the housing to selectively ignite the fuel upon application of an activating force to the activating unit; and at least two separate contact areas exposed through the housing to allow a user to use at least two fingers to apply forces to the contact areas which combined are greater than or equal to the activating force.
The two separate contact areas of the activating unit may be exposed through different portions or sides of the housing which can be on opposite sides of the housing. The activating unit can be made as a one-piece activating member and is moveably associated with the housing such that application of the force to the separate contact areas moves the activating member relative to the housing to selectively ignite the fuel.
The activating unit can alternatively be an activating assembly comprising a plurality of components at least one or more of which can be moveably associated with the housing to allow operation of the lighter through application of the required activating forces. Thus the activating unit can be a one-piece activating member or an actuating assembly comprising a plurality of parts.
The lighter may also have an extended nozzle as in a typical utility lighter and the nozzle is connected to the fuel supply. The fuel supply feeds fuel to the extended nozzle, typically through a tube. When the activating unit is moved or rotated, the internal surfaces of the activating unit interact with the gas release mechanism to release fuel, and interact with the ignition or spark generating member to create a spark so that the fuel may be ignited. The interaction can be direct or indirect as there could be a component between the cam and the piezo and or gas release mechanism.
The force required to move the activating unit to ignite the fuel can be a combination of the forces required to release the gas and activate the spark generating member. The force to move the activating unit can also be increased by adding an additional force imposing member, such as at least one spring that is opposing the movement of the activating unit, as well as return the activating unit to its initial position.
In addition to the possibility of adding an additional force imposing member to increase the necessary activating force, the activating force can also be adjusted to positioning of the contact areas relative to the pivot point, whereby the length of the lever for application of the ultimate force to the activating unit can be adjusted to make it easier or harder to activate the lighter.
A first contact area of the activating unit can be located on the bottom of the housing and the second contact area on a different portion of the handle. The second contact area is preferably located on the top portion of the handle. The activating unit can be moved from a first, initial or off position to a second or ignited position and when the activating unit is moved to the ignited position the lighter may ignite the fuel supplied from the fuel supply.
Preferred features of the present invention are disclosed in the accompanying drawings, wherein similar reference characters denote similar elements throughout the several views, and wherein:
c is a front view of the part of the ignition unit
Turning to
The utility lighter 10 of
Utility lighter 10 has a housing 100 having a handle at one end and a nozzle 230 (
Housing 100 may be formed primarily of molded-rigid-polymer or plastic materials such as acrylonitrile butadiene styrene (ABS) or the like. Housing 100 may also be formed of two-parts that are joined together by techniques known by those of ordinary skill in the art, such as ultrasonic welding.
Referring to
Referring to
Referring to
Suitable fuel supply containers 110 are disclosed in U.S. Pat. Nos. 5,934,895, 5,520,197, 5,435,719 and 6,086,360 the disclosure of which is incorporated herein by reference in its entirety. The fuel supply units disclosed in the above patents can be used with all of the disclosed components or with various components removed, such as windshields, latch springs, latches, and the like, as desired by one of ordinary skill in the art. Alternative arrangements of the fuel supply unit can also be used.
Tube 160 defines a channel for fluidly connecting fuel supply unit 110 to nozzle 165 (
Tube 160 is connected to nozzle 165 located adjacent to tip 230 of extended nozzle or wand 180. Tube 160 thus conveys fuel from fuel supply unit 105 to nozzle 165 at tip 230 of wand 180. Nozzle 165 may optionally include a diffuser 167, preferably in the form of a coil spring as shown in
Referring to
The piezoelectric unit 143 preferably includes an upper portion 140 and a lower portion 142 that slide with respect to each other along a common axis. A coil spring or piezo spring 148 is positioned between the upper and lower portions 140, 142 of the piezoelectric unit. Piezo spring 148 serves to resist the compression of piezoelectric unit, and when positioned in housing 100 resists rotation of cam 150.
Piezoelectric unit 143 (
Referring to
The shape of cam 150 can take any shape that has at least 2 exposed surfaces (150a & 150b,
Alternatively, the actuating unit may perform one of the fuel release and/or ignition function, and another mechanism or assembly may perform the other function.
It is within the broad scope of the present invention to have cam 150 or other embodiments of the actuating unit of the present invention operate either or both of the fuel release and ignition functions. In the embodiment shown in
Thus, any combination of the ignition and fuel supply functions can be controlled by the actuating unit in accordance with the broad scope of the present invention. It is preferred, however, to have the actuating unit control both of these functions.
The cam 150 for this embodiment can be is preferably an injection molded plastic component molded from thermoplastic materials such as acrylonitrile butadiene styrene (ABS), polypropylene, nylon, acetal, etc. or a die cast component cast from zinc (Zamak 3) or aluminum, etc.
Alternatively, cam 150 can be part of a multiple piece assembly such that the activating unit can be a multiple component assembly if desired, some or all of which may move relative to housing 100 and/or cam 150 to produce ignition as desired.
Alternatively, cam 150 can be produced with multiple materials such that the upper and lower activation surfaces 150c & 150d are covered with thermoplastic elastomer (TPE) to increase comfort for the intended user.
Referring to
Optionally, additional springs such as torsion spring 170a at pivot point 152 and/or spring 170c or the like can be added to create a different predetermined activative force. The predetermined force can also have a non-linear spring rate such that the force to rotate the cam 150 can change throughout the rotation if desired.
Torsion spring 170a can be located between housing 110 and cam 150. Torsion spring 170a is preferably manufactured from a metal having resilient properties, such as spring steel, stainless steel, or from other types of materials.
Spring 170c can be located between cam 150 and protrusion 220 on housing 100. Spring 170c can be a coil spring manufactured from a metal having resilient properties, such as spring steel, stainless steel, or from other types of materials such as an acetal thermoplastic. It should be noted that while spring 170c is shown mounted relative to protrusion 220 on the lighter housing 100 it may alternatively be coupled to other components of the lighter. In addition, coil spring 170b may be a tension or compression coil spring, or can be replaced with a leaf spring, a cantilever spring or any other biasing member suitable for biasing cam 150. Protrusion 220 may also have side walls, a pin or some other structure located on one surface of protrusion 220 that secures one end of spring 170b to prevent the spring from moving on protrusion 220 during rotation of the cam 150. Cam 150 may also have a recess (circular), or some other suitable structure to help maintain the other end of spring 170b in the desired position on cam 150 during rotation of cam 150.
Spring 170c can also be a variable spring rate spring to increase the force at a predetermined position, and this can be done to produce non-linear resistance to activation as described above. One predetermined position could be that the spring rate increases just prior to activation of the piezo. This can be accomplished by placing springs inside of each other, such that when the compressed height reaches the smaller spring the spring rate will be increased or a progressive rate coil spring can be used
Referring still to
Coil spring 170b is located between gas actuator 120 and rib retainer 190 on housing 100. Coil spring 170b is preferably manufactured from a metal having resilient properties, such as spring steel, stainless steel, or from other types of materials such as an acetal thermoplastic. It should be noted that while coil spring 170b is shown mounted against housing 100, it may alternatively be coupled to other components of the lighter.
Piezo spring 148, torsion spring 170a, coil spring 170b and/or spring 170c, can be adjusted to create a force difficult enough for unintended users to activate while adults can use two fingers such as their index finger and thumb to overcome the force necessary to ignite the lighter. The combined force on the exposed contact surfaces to ignite the gas should be less than 20 kg and greater 5 kg, preferably less than 15 kg and greater than 6.5 kg. In terms of torque, this could be adjusted by adjusting a lever length between contact areas of cam 150.
This embodiment (lighter design) is also inherently tamper-resistant. If cam 150 is removed from the lighter, the lighter is then non-functional and cannot be operated because all the required surfaces to release the gas and activate the ignition mechanism would be removed from the product.
Surfaces 150c and 150d can be designed to control the time in the rotation or angle of rotation at which fuel is released and the piezo mechanism is activated, by positioning the surfaces 150d and 150c relative to the piezo and/or fuel release components to engage where desired. The location of piezo mechanism 143, gas actuator 120, springs (170a, 170b & 170c) in relation to the cam pivot 152 and the force to activate the piezo mechanism 143, depress the gas actuator 120 to release gas, and rotate the cam to overcome the forces from springs (170a, 170b & 170c) plus any frictional forces combine to determine the force/torque to rotate cam 150 to ignite the fuel. When the user wants to extinguish the flame, releasing the activating unit allows internal springs to pivot cam 150 back to the starting or rest position, which stops the flow of gas from fuel supply unit 105 and thereby extinguishes the flame.
Thus, the embodiment of
It should be appreciated that rod 656 of this embodiment provides for a second surface to which force can be applied within the broad scope of the present invention as disclosed herein.
FIGS. 10 and 10A-D illustrate another embodiment which includes a push button 340 slidably connected to housing 100. Ribs 341 on push button 340 fit into slots in housing 100 (not shown) that allow push button 340 to slide in relation to the housing. Push button 340 has a pin 342 that fits into slot 351 on cam 350. As push button 340 is pushed by the intended user with one finger, pin 342 contacts a surface in slot 351 and a force/displacement is exerted on cam 350 to rotate cam 350 in a counter clock-wise direction at the same time the intended user can apply a force on lower exposed cam contact surface 350b with another finger to rotate cam 350. As cam 350 rotates, gas actuator contact surface 350d comes in contact and depresses gas actuator 120 to release gas from the fuel supply and piezo contact surface 350c depresses the piezo to create a spark to ignite the fuel.
Spring 170c is a coil spring located in a compressed state between protrusion 220 and surface 350c on cam 350 that increases the difficulty to rotate cam 350 and returns cam 350 to its initial position when released by the user. A pin 201 can be added to protrusion 200 to control the location of spring 170c on protrusion 220, or additional protrusions or recesses can be added to secure or engage on both sides of spring 170c as discussed above and as is known in the art.
Housing pin 325 prevents movement of cam 350 in a clockwise direction when cam 350 is in the initial position similarly to pin 225 in
The shape of slot 351 and pin 342 are designed such that the sliding motion of push button 340 does not cause any significant binding or interference between slot 351 and pin 342 such as to prevent cam 350 from returning to the initial position once push button and cam 350 are release by the end user. In addition, when cam 350 is rotated without depressing push button 340, push button 340 does not move until the back edge of slot 351 comes in contact with pin 342.
Summarizing the embodiment of FIGS. 10 and 10A-D, this embodiment functions on the same concept as the embodiment of
This embodiment can be operated either with a force applied to both push button 340 and cam 350 as intended, or through application of a greater magnitude force for individuals with sufficient strength, to either push button 340 or cam 350.
When sufficient force is applied, cam 350 will rotate within housing 100 in a counter-clockwise direction to the ignition position shown in
When it is desired to extinguish the flame from the lighter, the user can release the force being applied to cam 350 and push button 340, and the internal springs such as springs 170c and 170b cause cam 350 to pivot in a clockwise direction back to the initial position of
With respect to this and perhaps other embodiments of the present invention, it should be noted that after the lighter has been ignited, the flame can be maintained by continued force upon either of push button 340 or cam 350.
It should also be noted that with respect to this embodiment, slot 351 defines the amount of movement which can be imposed upon push button 340 before this movement exerts a force on cam 350. When moving from the initial position of
Aside from the shape of cam 150 as shown in
In another embodiment, as shown in
It should now be noted that pushbutton 440 could be configured as a cantilevered beam connected to the housing, and without the need for pivot 411. Resilience of the beam would allow the beam to flex and return as needed, and this resilience could also remove the need for spring 470c.
It should be appreciated that protrusion 442 on pushbutton 440 can interact with cam 450 in several different ways. Further, it is desired in this embodiment, as with other embodiments, that there be some play between pushbutton 440 and cam 450 so that it was not readily apparent to unintended users that there is some connection between these two structures.
When operating the lighter of this embodiment by applying force only to cam 450 or to both cam 450 and push button 440 with a higher force being applied to cam 450 then than to push button 440 such that contact occurs between surface 446 of push button 440 and surface 450e of cam 450 as cam 450 pulls push button 440 along with it during its rotation to the ignition position illustrated in
In either event, when it is desired to extinguish the flame in this embodiment, releasing push button 440 and cam 450 results in pivot of cam 450 rotating in a clockwise direction back to the initial position of
Still referring to
One of ordinary skill in the art will know and appreciate that the amount of force required may be varied by selecting different springs with a certain spring constant and/or modifying the geometry of camming surfaces of cam 150, as well as the location of center 152 in relation to the different contact points. As a result of this design, the force to rotate the cam 150 will also change.
The lighter is designed so that a user would have to possess a predetermined strength level in order to ignite the lighter. The lighter can also be ignited by the intended user with a single motion or a single finger by applying a greater force to one of the exposed surfaces 150a or 150b, and this can be referred to as a high force mode.
With respect to all embodiments, in order to make the lighter so that it is not excessively difficult for some intended users to actuate, the high force mode preferably should not be greater than a predetermined value. It is contemplated that for the lighters of this invention, the preferred value is less than about 10 kg and greater than about 5 kg, and more preferably less than about 8.5 kg and greater than about 6.5 kg. In other words, the total force necessary to be applied to the two contact surfaces, either in combination or entirely on one or the other, should be between about 5 and about 10 kg. It is believed that such a range of force would not substantially negatively affect use by some intended users, and yet would provide the desired resistance to operation by unintended users. These values are exemplary and the operative force in the high force mode may be more or less than the above ranges.
Alternatively, if the intended user does not wish to use the lighter by activating the lighter with one finger at one contact surface (high force mode), the intended user may operate the lighter by contacting multiple cam surfaces depending upon the embodiment, and applying force at both locations simultaneously requiring less force at any one location to activate the lighter and making it easier to operate. This mode of operation comprises multiple actuation movements, and in the embodiment shown, the user applies two or more forces/motions to move the cam 150, 350, 450, 650 and/or pushbutton 340, 440 or extending rod 656 with less force at any one surface than would need to be applied in the high force mode, and this can be referred to as the low force mode.
Preferably, in order to perform the low force mode, the user has to possess a predetermined level of dexterity, hand size and cognitive skills to move both exposed contact surfaces (150a and 150b for example) at the same time.
The present invention is not limited to the sequences disclosed but also includes such alternatives as contemplated by one of ordinary skill in the art. The unintended user safety features of lighter 10 in the low-force mode also may rely on the physical differences between intended and unintended users, for example, by controlling the spacing between the exposed surfaces of cam 150, 350, 450 (and/or push button 340/440) and/or adjusting the operation forces and displacements required to activate the lighter. The forces and displacements can be modified by adjusting each cam surface interaction, by adjusting the location of the center of cam 150, the shape of the cam surfaces (150c & 150d), the spring designs, etc. Further, Gaps Y, Z and thicknesses A & B can also be configured to optimize feel and/or the forces and displacements required to activate the lighter for intended and unintended users.
The design of the internal components and/or assemblies, for example the configuration of the actuating assembly or unit, the configuration of any linking mechanism, the number of springs and forces generated by the springs all affect the force which a user needs to apply to the actuating unit in order to operate the lighter. For example, the force requirements for a cam which moves along an actuation path may not equal the force requirements to move an actuating unit along a linear, rotational, non-linear, etc. actuation path. Actuation may require that a user move the actuating unit along multiple paths which may make actuation more difficult.
While the embodiments disclosed have shown preferred actuating units with a rotational actuation path, one of ordinary skill in the art can readily appreciate that a linear, rotational, and/or non-linear actuation, multiple paths, etc. are contemplated by the present invention.
One of ordinary skill in the art can readily appreciate that various factors can increase or decrease the force which an intended user can comfortably apply to the cam. These factors may include, for example, the leverage to push, pull or actuate the actuating unit provided by the lighter design, the friction and spring coefficients of the lighter components, the shape of the exposed cam surfaces, the cam shape, the complexity of the cam actuation motion, the location, size and shape of the components, intended speed of activation, etc. For example, the location and/or relationship between the cam exposed surfaces can be configured taking into account whether the user has large or small hands.
One feature of lighter 10 is that in the high-force mode single actuating point/operation may be performed so long as the user provides the necessary actuation force and displacement. Another feature of the lighter 10 is that in the low-force mode multiple actuating points/operations may be performed so long as the user applies enough force(s) and displacement(s) required at the exposed surfaces of cam 150 necessary to ignite the lighter. In particular, if the lighter does not operate on the first attempt, the user may re-attempt to produce a flame by actuating cam 150 by applying a force to either a single or to multiple actuation points which may require releasing the actuating unit for example to reset the piezo.
The lighter designs as shown in
In all embodiments disclosed herein, lighter 10 has two activation surfaces that have to be moved in certain directions with enough force and displacement to ignite the lighter. This allows the adult user to apply forces at different points to the same component or assembly to overcome the forces to ignite the lighter. By locating the activation points of cam 150 such that two different fingers of the intended user can apply the force to ignite the lighter, the unintended user will have difficulty because they do not have the cognitive ability, dexterity, hand size, and/or strength to overcome the force to activate the lighter by only contacting one activation point, or may not be able to reach two or more activation points with a smaller hand size than an adult or intended user as well as apply enough force in the correct direction at the same time to activate the lighter.
Distance between the activating points can be designed such that it requires 2 hands to activate or a large hand to reach both activation points at the same time.
The lighter is preferably designed with a rotating cam with two separate activation points that can be contacted by an adult hand that requires a predetermined torque. For typical lever arm lengths of lighters of the type to which the invention, having lever arms between about 5 mm and about 50 mm, the predetermined torque is preferably less than 500 kg-mm and greater than 50 kg-mm. The two points would preferably be positioned for contact by the index finger and the thumb. The index finger can rotate cam 150, 350, 450 and the thumb can apply displace push button 340, 440 a predetermined distance to ignite the lighter as shown in
As force is applied to cam 150, 350, 450 (and/or push button 340, 440), cam 150, 350, 450 (and/or push button 340, 440) rotates to depress (rotate) the gas actuator 120 and depress the piezo mechanism 143 as shown in
It should also be noted that the terms “first”, “second”, “third”, “upper”, “lower”, and the like may be used herein to modify various elements. These modifiers do not imply a spatial, sequential, or hierarchical order to the modified elements unless specifically stated.
While the present disclosure has been described with reference to one or more exemplary embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for the elements thereof without departing from the scope of the present disclosure. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the disclosure not to be limited to the particular embodiment(s) disclosed as the best mode contemplated, but that the disclosure will include all embodiments falling therein.