Abstract:
A micromechanical device that takes a vertical force to a micro substrate that results into a vertical motion and translates that vertical motion into horizontal motion. A pit is etched onto a micro substrate where the walls of the pit meet the floor of the pit at less than a 90° angle. A vertical force is applied to a structure to push it along the angled wall of the pit and as the structure reaches the bottom of the pit the vertical motion is translated into horizontal motion. By attaching a spring or similar mechanism to the structure, one can store the horizontal momentum for later use by latching the structure in some way before the spring can pull the structure back into its original position.

Description:
STATEMENT OF GOVERNMENT INTEREST 
     The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without payment of any royalties thereon or therefor. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention is micromechanical device on the order of 100 μm to 10 mm for translating force normal to a plane into motion along said plane. Throughout the remainder of this application, the term vertical means approximately normal to a plane and the term horizontal means approximately parallel or approximately along the plane of a substrate of the device described herein. More particularly, the device receives a vertical force and translates the energy from that force for use in the horizontal plane. The device can easily be employed as part of a micro-actuator system. 
     2. Description Of The Related Art 
     Many products manufactured today require the use of micromechanical devices in order to meet size and weight requirements. Many of these micromechanical devices are used as actuators or trigger mechanisms that apply forces to a multitude of components in order for the products to function. These devices are extremely small, on the order of 100 μm to 10 mm, and are normally manufactured on a flat substrate or “chip.” In order for these micromechanical devices to function as actuators, a force must be applied to the devices so they, in turn, can apply this force to the mechanism they are designed to actuate. Current devices use a myriad of forces to accomplish this task including electrostatic forces, magnetic forces, and gravitational forces. 
     Because of the sizes at issue, the devices normally operate in the horizontal plane along the substrate upon which they are manufactured. Therefore, these devices exert the required forces along the substrate in order to obtain the required result from the device. 
     However, due to the design of certain machinery and equipment, it is sometimes far more effective or efficient to apply the required forces to the chip vertically. But in order for vertical forces to be useful along the substrate, one must convert the vertical motion resulting from the vertical force into horizontal motion. One example of equipment wherein applying vertical forces to a horizontal microactuator would be more effective and efficient is munitions used by the military. Because of weight and energy restrictions in munitions, micromechanical devices have been incorporated to arm the munitions. However, the optimum design of these munitions places the substrate of the micromechanical device in a horizontal position. When the munitions are fired or launched, a large amount of vertical force occurs throughout the munitions. This vertical force cannot be used to engage the micromechanical device in current systems. 
     SUMMARY OF THE INVENTION 
     The invention consists of a micromechanical device for translating vertical force to horizontal movement, comprising a substrate having a surface, a recess formed within the surface, having a wide section with an opening formed coplaner to the surface, with at least one side wall extending at an angle of about 90° or less from the opening of the wide section, and at least one narrow section extending from the wide section through the side wall, and, at least one structural member comprising a mass proximate to the side wall, the mass wider than the narrow section of the recess and sufficiently narrow to at least partially enter the wide section of the recess, a positioning system attached to the mass and aligned proximate to the narrow section of the recess, means for exerting a horizontal force on the mass, approximately coplaner with the surface, attached to the positioning system, and, means for exerting a vertical force on the mass, approximately perpendicular to the surface, sufficient to force the mass along the side wall, thereby engaging the horizontal force means. 
     The invention also includes of a method for arming a warhead, comprising the steps of inserting means for igniting the warhead within the warhead, inserting a micromechanical device such as that translates vertical movement to horizontal movement within the warhead comprising a substrate having a surface, a recess formed within the surface, having a wide section with an opening formed coplaner to the surface, with at least one side wall extending at an angle of about 90° or less from the opening of the wide section, and at least one narrow section extending from the wide section through the first side wall, and, at least one structural member comprising a mass proximate to the side wall, the mass wider than the narrow section of the recess and sufficiently narrow to at least partially enter the wide section of the recess, a positioning system attached to the mass and aligned proximate to the narrow section of the recess, means for exerting a horizontal force on the mass, approximately coplaner with the surface, attached to the positioning system, sufficient to align the structural member to engage the ignition means, and, launching the warhead to provide a vertical force, approximately perpendicular to the surface, sufficient to move the mass along the side wall, thereby engaging the horizontal force means wherein alignment of the structural member results in ignition. 
     The invention still further consists of micro horizontal movement translated from a vertical force applied to the surface of a substrate produced from the process comprising the steps of forming a micro recess within the surface, having a wide section with an opening formed coplaner to the surface, with at least one side wall extending at an angle of about 90° or less from the opening of the wide section, and at least one narrow section extending from the wide section through the side wall, placing at least one structural member proximate to the micro recess comprising a mass proximate to the side wall, the mass wider than the narrow section of the recess and sufficiently narrow to at least partially enter the wide section of the recess, a positioning system attached to the mass and aligned proximate to the narrow section of the recess, and, means for exerting a horizontal force on the mass, approximately coplaner with the surface, attached to the positioning system, and, exerting a vertical force on the mass, approximately perpendicular to the surface, sufficient to force the mass along the side wall, thereby engaging the horizontal force means. 
     Accordingly, it is the object of this invention to provide a micromechanical device that translates a vertical force into horizontal movement. 
     It is a further object of this invention to produce a micromechanical device that can use the vertical force produced by a munition, missile, or warhead upon lift-off in order to arm said munition, missile, or warhead. 
     This invention accomplishes these objectives and other needs requiring translation of vertical force to horizontal movement on the micro scale. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the invention, and, together with the description, serve to explain the principles of the invention. 
     FIG. 1 is a cross sectional, side view of one embodiment of the invention comprising one structural member. 
     FIG. 2 is top view of the same embodiment of the invention set forth in FIG.  1 . 
     FIG. 3 is a top view of an alternative embodiment of the invention comprising two structural members and two locks. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     The invention, as embodied herein, comprises a micromechanical device on the order of 200 to 500 microns for translating vertical force into horizontal motion. The device is manufactured on a micro substrate placed in a horizontal plane. The device operates by placing a mass on the surface of the substrate and connecting the mass to a positioning system. The positioning system, in turn, is connected to a spring or other horizontal force means that is attached to the surface. The positioning system allows horizontal movement of the mass along the surface or vertical movement of the mass perpendicular to the surface. The spring or horizontal force means applies a horizontal force on the mass when the mass moves in the horizontal plane. A recess is formed within the surface comprising a wide section and a narrower section extending through an angled wall of the wide section. The mass is placed proximate to the angled wall of the wide section of the recess so the positioning system is proximate to the narrower section of the recess. When a vertical force is applied to the mass, the mass is forced along the angled wall of the recess so the angle of the wall forces the mass to move both vertically and horizontally. The narrower section of the recess ensures that the positioning system does not impede the movement of the mass into the wide section of the recess. Because the angled wall forces the mass to move partially in the horizontal plane, the spring or other horizontal force means is engaged and the resultant horizontal movement can be used for myriad purposes. 
     Referring to FIG. 1, one preferred embodiment of a micromechanical device for translating vertical force to horizontal movement comprises a substrate  102  having a surface  104 . A recess  106  is formed within the surface  104  having a wide section  106   a  with an opening  108  formed coplaner to the surface  104 . The wide section  106   a  has least one side wall  110 , extending at an angle of about 90° or less from the opening  108 . The recess  106  also has at least one narrow section  112  extending from the wide section  106   a  through the side wall  110 . The device also comprises at least one structural member  114 . The structural member  114  comprises a mass  116 , proximate to the side wall  110 , wider than the narrow section  112  and sufficiently narrow to at least partially enter the wide section  106   a . The structural member  114  further comprises a positioning system  118  attached to the mass  116  and aligned proximate to the narrow section  112 . The positioning system is connected to a means for exerting a horizontal force  120  on the mass  116 , approximately coplaner with the surface  104 . The structural member  114  also comprises a means for exerting a vertical force  122  on the mass  116 , approximately perpendicular to the surface  104 , sufficient to force the mass  116  along the side wall  110 , thereby engaging the horizontal force means  120 . 
     The size of the substrate  102  is on the micro level. This normally comprises areas from about 100 μm to about 10 mm. The recess  106  will be formed within the surface  104  normally through etching, a standard process used in the manufacture of micro substrates. The wide section  106   a  comprises preferably from about 1 square millimeter or less or more preferably from about  0 . 16  square millimeters to about 0.25 square millimeters. The wide section  106   a  also comprises at least one side wall  110  which is at an angle of less than 90° from opening  108 . In one preferred embodiment of the invention, the wide section  106   a  further comprises a floor  126  approximately parallel to the surface  104 . The recess  106  also comprises at least one narrow section  112  which extends through the side wall  110  which is, again, portrayed by a dashed line in FIG.  1 . FIG. 2 more clearly shows the narrow section  212  through a top view extending from the wide section  206   a  which is characterized by a dashed line in FIG. 2 . In some preferred embodiments of the invention, there are a plurality of side walls having a corresponding plurality of narrow sections extending through the side walls. For example, referring to FIG. 3, two narrow sections  312   a  and  312   b  extend from the wide section  306  through two side walls  310   a  and  310   b.    
     Referring again to FIG. 1, the structural member  114  is shown by a dashed line above the narrow section  112 . The mass  116  may comprise a proof mass or numerous other objects. In one preferred embodiment of the invention, the mass  116  comprises a shape sufficiently narrow to at least partially contact the floor  126  of the wide section  106   a . The positioning system  118  ensures that the mass  116  maintains its position prior to engaging the device. The positioning system  118  preferably comprises a rigid structure such as a cantilever beam. In one preferred embodiment of the invention, as set forth in FIG. 3, the mass  316   a  and  316   b  and the positioning system  314   a  and  314   b  comprise a unitary T-shaped form. Referring again to FIG. 1, the horizontal force means  120  preferably attaches to the positioning system  118  and fixes to the surface  104  to exert a horizontal force upon the mass  116  when the mass  116  moves horizontally. The horizontal force means  120  preferably comprises a spring or other elastic type of system that when pulled exerts a force opposite to the pull. In one preferred embodiment of the invention, the horizontal force means  120  imparts a force approximately aligned with the narrow section  112  and away from the wide section  106   a . Therefore, when a vertical force means, portrayed by arrow  122 , approximately perpendicular to the surface  104 , is applied to the mass  116 , the vertical force means  122  forces the mass  116  along the side wall  110 , and the horizontal force means  120  stretches; when sufficient stretching occurs or the vertical force means  122  stops, the horizontal force means  120  moves the structural member  114  horizontally. The vertical force means  122  may be provided in any manner but preferably comprises the force resulting from launching a warhead. In some preferred embodiments of the invention, a plurality of structural members can be employed that may be positioned corresponding to the plurality of side walls and narrow sections noted above. 
     Another embodiment of the invention further comprises means for latching  124  the mass  116  within the recess  106  to change the horizontal movement of the structural member  114  produced through the horizontal force means  120 . The latching means  124  may also reduce the speed or amount of the horizontal movement. The latching means  124  may hold the structural member to delay the horizontal movement produced by the horizontal force means  120 . The latching means  124  may comprise simple hook and release mechanisms or interlocking shaped mechanisms, however, a more preferred embodiment of the latching means  124  is set forth in FIG.  3 . In FIG. 3 the latching means  324  comprises a second side wall  310   b , opposite the side wall  310   a , having a corresponding narrow section  312   b  and a corresponding structural member  314   b . In this embodiment the horizontal force means  320   b  of the second side wall structural member  314   b  provides less force than the horizontal force means  320   a  of the structural member  314   a . The latching means  324  also comprises a means for attaching the mass of the second side wall structural member  314   b  to the structural member  314   a  upon contact of the two corresponding masses,  316   a  and  316   b , characterized by the interlocking mechanism  330 . In this embodiment, the horizontal force means  320   b  provides more force in opposition to horizontal force means  320   a , thereby causing greater horizontal movement in the direction of the horizontal force means  320   a . A more complex embodiment of the invention may comprise a plurality of side walls having a corresponding plurality of narrow sections and a corresponding plurality of structural members noted above wherein the horizontal force means of the plurality of structural members provide varying amounts of force, and, means for attaching the masses of the plurality of structural members to the mass of the structural member upon contact of the masses. This embodiment of the invention would allow one to provide the horizontal movement in numerous directions and amounts. 
     Referring to FIG. 3, this preferred embodiment of the invention also comprises a first lock  332  capable of holding the structural members  314   a  and  314   b  substantially immobile. In the embodiment of the invention depicted, the first lock  332  holds the structural member  314   b  substantially immobile. Under vertical loading, the structural member  314   a  attaches to structural member  314   b  through the latching means  330 , the first lock  332 , also vertically actuated, releases structural member  314   b . Until release of the first lock  332 , the horizontal force means  320   a  and  320   b  may not act upon the device. In one preferred embodiment of the invention the first lock  332  comprises a hook mechanism releasable through the vertical force means. . However, the first lock  332  may comprise any means capable of holding the structural members  314   a  and  314   b  substantially immobile until release. The embodiment of the invention shown in FIG. 3 also comprises a second lock  334 , independent of the first lock  332 , that, when engaged, allows the two structural members  314   a  and  314   b  to move a predetermined distance. This second lock  334  allows some horizontal movement through the horizontal force means  320   a  and  320   b , but does not allow all of the horizontal force stored in said means to be released. The second lock  334  would be released through a different mechanism than the first lock  332 . Upon release of the second lock  334 , the remaining horizontal force stored within the horizontal force means  320   a  and  320   b  would result in further horizontal movement. In one preferred embodiment of the invention the second lock  334  comprises a thermal actuator capable of releasing the second lock  334 . This type of double locking scheme can be used for many purposes including part of a method for arming a warhead which is described below. 
     Although there are many applications for the micromechanical device described above, one preferred use is to assist in arming a warhead. The device set forth in FIG. 1 may be used in a method for arming a warhead. The first step in said method comprises inserting means for igniting the warhead into the warhead. Any standard method of igniting the warhead may be used. The second step in said method comprises inserting a micromechanical device, such as that shown in FIG. 1, that translates vertical force to horizontal movement within the warhead. The device comprises a substrate  102  having a surface  104 , a recess  106  formed within the surface. The recess  106  has a wide section  106   a  with an opening  108  coplaner to the surface  104 . The recess also has at least one side wall  110  extending at an angle of about 90° or less from the opening  108  and at least one narrow section  112  extending from the wide section  106   a  through the first side wall  110 . The device also contains at least one structural member  114 . The structural member comprises a mass  116  proximate to the side wall  110 , the mass  116  wider than the narrow section  112 , and sufficiently narrow to at least partially enter the wide section  106   a . The structural member  114  also contains a positioning system  118  attached to the mass  116  and aligned proximate to the narrow section  112 . The structural member  114  also comprises means for exerting a horizontal force  120  on the mass  116 , approximately coplaner with the surface  104 , attached to the positioning system  118 . The horizontal force means  120  must be sufficient to align the structural member  114  to engage the igniting means. The final step of said method comprises launching the warhead to provide a vertical force  122 , approximately perpendicular to the surface  104 , sufficient to move the mass  116  along the side wall  110 . Movement of the mass  116  engages the horizontal force means  120  wherein alignment of the structural member  114  results in ignition. This method for arming a warhead may also use the double locking scheme described above. The steps for including this locking scheme are shown by the locking mechanisms illustrated in FIG.  3 . The first step comprises applying a vertical force, releasing the first lock  332  that holds the structural members  314   a  and  314   b  substantially immobile; simultaneously, the vertical force is converted to horizontal force and stored in the horizontal force means  320   a  and  320   b . The second lock  334 , when engaged, allows the structural members  314   a  and  314   b  to move a predetermined distance. In a preferred embodiment of the method, this would be accomplished by launching the warhead to provide a vertical force that would release the first lock  332  and store horizontal force in the horizontal force means  320   a  and  320   b . This results in the structural members  314   a  and  314   b  moving a predetermined distance to prime the warhead. The final step comprises releasing the second lock  334  allowing structural members  314   a  and  314   b  to move to an armed position. This results in arming the warhead for ignition 
     The embodiment of the micromechanical device set forth in FIG. 1 may also be used as part of a process for translating a vertical force  122  applied to the surface  104  of a substrate  102  to micro horizontal movement. The first step of this process comprises forming a recess  106  within the surface  104 , having a wide section  106   a  with an opening  108  formed coplaner to the surface  104 . The wide section  106   a  has at least one side wall  110  extending at an angle of about 90° or less from the opening  108  and at least one narrow section  112  extending from the wide section  106   a  through the side wall  110 . The second step of the process comprises placing at least one structural member  114  proximate to the recess  106 . The structural member  114  comprises a mass  116  proximate to the side wall  110 . The mass  116  is wider than the narrow section  112  and sufficiently narrow to at least partially enter the wide section  106   a . The structural member  114  also comprises a positioning system  118  attached to the mass  116  and aligned proximate to the narrow section  112 . The structural member must also comprise means for exerting a horizontal force  120  on the mass  116 , approximately coplaner with the surface  104 , attached to the positioning system  118 . The final step of the process comprises exerting a vertical force  122  on the mass  116 , approximately perpendicular to the surface  104 , sufficient to force the mass  116  along the side wall  110 . The horizontal movement of the mass  116  engages the horizontal force means  120  to create horizontal movement in the opposite direction to the movement of the mass  116 . 
     What is described are specific examples of many possible variations on the same invention and are not intended in a limiting sense. The claimed invention can be practiced using other variations not specifically described above.