Abstract:
A generally cylindrical body of a device such as a cam lock is provided with a snap-in mount that enables the body to be mounted from one side of and through mounting holes formed in support panels of distinctly different thicknesses. The body has a shoulder that faces in one direction toward one side of a support panel, and carries sets of movable arms that define engagement surfaces located at different distances from the shoulder that snap outwardly after being inserted through a panel mounting hole to face toward the opposite side of the support panel. The body can be mounted on panels having three different thicknesses if three sets of arms are provided that each define engagement surfaces located at a different distance from the shoulder. More panel thicknesses can be accommodated if one or more of the sets of arms define two or more sets of engagement surfaces each located at a distinctly different distance from the shoulder.

Description:
REFERENCE TO SUBJECT-MATTER-RELATED DESIGN APPLICATION 
     Reference is made to design application Ser. No. 29/136,082 filed Jan. 24, 2001 by Timothy P. Laabs et al entitled HOUSING PORTIONS OF A CAM LOCK which discloses appearance features that may be utilized in practicing the present invention, the disclosure of which is incorporated herein by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a snap-in mount for mounting a generally cylindrical body of a device such as a cam lock in holes formed through support panels that differ in thickness. More particularly, the present invention relates to a generally cylindrical body of a cam lock or the like that defines a shoulder for facing toward and engaging one side of a support panel, and that defines an insertion portion which extends away from the shoulder and is configured to be moved along an axis of and inserted through a panel mounting hole, with a plurality of arms being connected to the body for defining arm portions that spring radially outwardly from the insertion portion after the insertion portion hats been inserted through the hole to provide engagement surfaces for engaging the opposite side of the panel, with the engagement surfaces being located at differing distances from a plane in which the shoulder engages the one side of the support panel so that the body can be securely mounted on panels having thicknesses that substantially equal one of these differing distances. 
     2. Prior Art 
     Snap-in mounting arrangements for installing small devices such as latches, locks, indicator lights, electrical switches and the like in holes formed through support panels are well known. Often the device to be installed has a generally cylindrical body with a bezel or other type of body formation that defines a shoulder for facing toward and engaging one side of a support panel, with the opposite side of the support panel being engaged by elements that are movably carried by the body and biased to snap radially outwardly after being inserted at least part way through a support panel hole. 
     Some previously proposed snap-in mounts employ a pair of opposed, radially outwardly biased elements such as arms that are formed integrally with a body that is molded from plastics material, wherein the arms take advantage of the so-called “memory” of the plastics material to provide a biasing action that is sufficient to snap the arms radially outwardly (after the arms have passed at least part way through a mounting hole formed in a support panel during installation of the body on the support panel), whereafter the arms are retained by the “memory” of the material in their outwardly extended positions where they engage the rear face of the support panel. These “snap-out” elements typically are connected to other portions of the body by regions of relatively thin cross-section that can be flexed to permit the elements to move radially inwardly a sufficient amount to permit passage through a mounting hole. Since the thin cross-sections normally are flexed only once (or only a very limited number of times) during installation of the body on a support panel, the flexed cross-sections usually do not break, and usually retain sufficient strength to be capable of retaining the snap-out elements in their radially outwardly extended positions for holding their associated devices in installed positions on support panels throughout relatively lengthy service lives. 
     In an effort to accommodate support panels of slightly differing thicknesses, it also is known to provide each of the snap-out elements (of the snap-in mounts of devices to be installed in mounting holes formed through the support panels) with a rack of small tooth-like formations. The tooth-like formations do not feature a design that is optimized for use with a particular panel thickness; rather, these formations are intended to grip, as best they can, support panels within a narrow range of thicknesses, typically to accommodate a range of tolerances such as may be needed if support panels intended to be of generally the same thickness are being provided by a plurality of suppliers. Thus, one drawback associated with utilizing sets of small tooth-like formations on the snap-out elements of a snap-in mount is the fact that the “teeth” do not feature a design that is optimized to work with any particular support panel thickness. A further drawback resides in the fact that the range of panel thicknesses that the tooth formations are designed to serve usually is quite limited, whereby panel thicknesses that vary significantly one from another are not well accommodated by this approach. 
     A further limitation that results from utilizing sets or racks of small tooth-like formations on the snap-out elements of snap-in mounts is that the small size of the teeth, and the fact that relatively few of the teeth actually grip a support panel, can cause the resulting grip of the device on the support panel to be lacking in “meat.” Weak grips provided by small teeth can loosen with time as the plastic material from which the teeth are formed tends to wear away, with sharp edges that may enhance the grip tending to “round off” so as to conform better to the shape of the panel that is being gripped by the teeth. The resulting relatively weak grips often can be defeated by force, which can permit security devices such as cam locks and switch locks to be pulled from their mounting positions so that the functions they serve can be defeated or bypassed. 
     Still another problem often not well addressed by the snap-in mounts of prior proposals is the fact that inexpensively formed mounting holes formed in support panels of lockable thermostat covers (and other kinds of low-security equipment covers and the like) can vary significantly in size, which may cause the bodies of devices installed in these holes to fit quite loosely. Undesirable movements and rattling noise may result during use, especially in the presence of vibration. The use of only one pair of oppositely biased snap-out elements that engage only small regions of a support panel at locations on opposite sides of a mounting hole may serve to limit body movement in the opposite directions (that reside within a plane that includes the opposite directions) in which the elements are biased, but tends to do little to limit vibratory movements of the body in other directions (i.e., in directions that are transverse to the plane that contains the opposite directions in which the snap-out elements are biased by the “memory” of the plastics material from which these elements are formed). While some proposals call for the use of auxiliary biasing devices such as springs to intensify the biasing action in an effort to minimize vibration, the fact that the resulting biasing action operates only in a single plane (namely the plane that contains the opposite directions of the biasing action of the oppositely biased pair of snap-out elements) still does little to quell body movements in directions that are transverse thereto. 
     SUMMARY OF THE INVENTION 
     The present invention addresses the foregoing and other needs and drawbacks by providing a snap-in mount for mounting a generally cylindrical body of a device such as a cam lock, a switch lock, an indicator light or the like in holes formed through support panels that differ in thickness. In one form of the invention, the body is configured to define a shoulder for facing toward and engaging one side of a support panel, and an insertion portion which extends away from the shoulder and is configured to be moved along an axis of and inserted through a panel mounting hole. A plurality of arms are connected to the body for defining arm portions that spring radially outwardly from the insertion portion after the insertion portion has been inserted through the hole to provide engagement surfaces for engaging the opposite side of the panel. The engagement surfaces are located at differing distances from a plane in which the shoulder engages the one side of the support panel so that the body can be securely mounted on panels having thicknesses that substantially equal one of these differing distances. 
     In another form of the invention, a snap-in mount is provided for a device that adapts a body of the device to be mounted from one side of and through a: hole formed in a support panel to secure the device to the panel. A shoulder of the device faces in one direction toward the panel for engaging the one side of the panel. A plurality of engagement surfaces also are defined by the device that face in an opposite direction for engaging an opposite side of the panel when the shoulder engages the one side of the panel, with distances between the engagement surfaces and a plane in which the shoulder engages the one side of the panel differing sufficiently to enable the device to be mounted on panels of distinctly different thicknesses. The body of the device has an insertion portion that is configured to be positioned and moved along an axis of the hole so as to be inserted through the hole from the one side of the panel to an installed position where the shoulder of the device faces toward and engages the one side of the panel. A plurality of sets of arms are connected to the body, with each of the arms having an arm portion that is movable inwardly toward the axis and outwardly away from the axis when the body is positioned along the axis. Each of the arm portions is configured, when moved inwardly toward the axis, to pass at least part way through the hole when the insertion portion of the body is moved along the axis to the installed position. Each of the arm portions is configured, when moved outwardly away from the axis, to define an engagement surface that faces in the one direction toward said plane. The engagement surfaces defined by the arm portions of one of the sets of arms are spaced a substantially equal distance from said plane that differs from another distance at which the engagement surfaces defined by the arm portions of at least one of the other sets of arms is spaced from said plane. The arms are connected to the body in a manner that causes the arm portions to normally extend outwardly from the insertion portion of the body to positions located away from the axis, and in a manner that causes the arm portions to be biased toward these extended positions when the arm portions are pressed inwardly toward the axis to permit the insertion portion of the body to pass through the hole so as to cause the arm portions of at least one of the sets of arms to move outwardly away from the axis once the insertion portion has been moved to the installed position to cause the engagement surfaces thereof to face in said opposite direction toward said opposite side of the panel so that the one and opposite sides of the panel are engaged by the shoulder and by selected ones of the engagement surfaces of such ones of the arm portions as have moved outwardly away from the axis after passing at least part way through the hole. By this arrangement, the device can be securely mounted on panels of differing thicknesses that each substantially equal one of the differing distances. 
     In another form of the invention, a cam lock has a body 1) that extends along an imaginary central axis, 2) that defines a shoulder which faces in one direction along the axis and extends in a shoulder plane that perpendicularly intersects the axis for engaging one side of a panel on which the cam lock is to be mounted, 3) that has a generally cylindrical insertion portion of the body that extends in said direction along the axis away from the shoulder and that is configured to be inserted into and to pass at least partially through a mounting hole formed through the panel, and 4) that carries arms arranged in opposed pairs on opposite sides of the axis with the arms of one of the pairs being spaced circumferentially about the body from the arms of others of the pairs. The arms define arm portions 1) that travel at least part of the way through the mounting hole when the insertion portion of the body is inserted into the mounting hole to an installed position of the body wherein the shoulder engages the one side of the panel, 2) that are movable radially inwardly and outwardly relative to the body, and 3) that are biased outwardly toward extended positions relative to the body, with the arm portions of each pair of arms being operative when in the extended positions thereof to define engagement surfaces that face in an opposite direction along the axis toward the shoulder plane for engaging an opposite side of the panel, and with the engagement surfaces of one of the pairs of arms extending in at least one plane that perpendicularly intersects the axis at at least one distance from the shoulder plane that differs from at least one other distance at which a plane in which the engagement surfaces of another of the pairs of arms perpendicularly intersects the axis, to thereby enable the engagement surfaces of the one and another pairs of arms to cooperate with the shoulder to grip panels of differing thicknesses when the body is in installed positions in mounting holes defined by said panels of differing thickness. 
     One novel feature of the present invention resides in the use it makes of a plurality of sets of body-carried snap-out elements to define engagement surfaces that extend in different planes spaced along a central axis of the body from a body-defined shoulder to accommodate support panels of distinctly different thicknesses that substantially equal the distances between the plane of the shoulder and the planes of the engagement surfaces. Other novel features also are present, as is exemplified by the use that may be made of a plurality of sets of outwardly biased snap-out elements to engage support panel material that surrounds mounting holes to minimize vibratory movements of the bodies that are installed in the holes. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     These and other features, and a fuller understanding of the invention may be had by referring to the following description and claims, taken in conjunction with the accompanying drawings, wherein: 
     FIG. 1 is a perspective view of a cam lock having a body provided with a snap-in mount that enables the body to be installed in holes formed through support panels of a variety of thicknesses; 
     FIG. 2 is a right side elevational view thereof; 
     FIG. 3 is a rear view of the body thereof, as seen from a plane indicated by a line  3 — 3  in FIG. 2; 
     FIG. 4 is a sectional view seen from a plane indicated by a line  4 — 4  in FIG. 3, with the body shown installed in a hole formed through a support panel of a relatively thin first thickness; 
     FIG. 5 is a sectional view seen from a plane indicated by a line  5 — 5  in FIG. 3, with the body shown installed in a hole formed through a support panel of a second thickness that is significantly greater than the first thickness; 
     FIG. 6 is a sectional view seen from a plane indicated by a line  6 — 6  in FIG. 3, with the body shown installed in a hole formed through a support panel of a third thickness which is greater than the first thickness and less than the second thickness; and, 
     FIG. 7 is a sectional view showing the same features that are depicted in FIG. 6 except that the body is shown installed in a hole formed through a support panel of a fourth thickness which is greater than the first, second and third thicknesses. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     While the drawings depict the snap-in mount of the present invention embodied in a so-called “cam lock,” it will be understood that the snap-in mount of the present invention can be employed to install the generally cylindrical bodies of a variety of key-operated devices such as key-operated locks and key-operated electrical devices such as switches on support panels of a variety of thicknesses, and to install a variety of other kinds of devices such as indicator lights, microphones, speakers, non-key-operated switches and the like on support panels of a variety of thicknesses. 
     It also should be understood that the snap-in mount of the present invention is seldom well suited for use in so-called “high security” applications. A “low security” application for which the snap-in mount of the present invention is well suited is to hold closed such covers or guards as may be used to shield wall-mounted thermostats in public buildings where it is desirable to shield sensitive thermostat controls from being accidentally hit by building occupants, and to restrict access to to these controls to those who are authorized to adjust their settings. The snap-in mount of the present invention can be used in applications such as this to mount simple cam locks on “support panels” such as removable plastic thermostat covers to accomplish non-critical shielding and non-critical access control functions of this general nature. 
     Turning now to FIGS. 1 and 2, a cam lock  110  is shown which has a body  120  that protectively encloses a key-operated plug  130 . The plug  130  extends through the body  120  along a central axis  100 . The plug  130  has a threaded rear region  132  which projects rearwardly from the body  120  to support a hook-shaped cam  140  and a lock-nut  150 . 
     The cam lock  110  operates in a manner that is well known to those who are skilled in the art in that, after the body  120  has been suitably mounted in a hole (such as one of the mounting holes  111 ,  112 ,  113 ,  114  that are formed through the panels  101 ,  102 ,  103 ,  104 , as is depicted in FIGS. 4,  5 ,  6 ,  7 , respectively), a suitably configured key (not shown) can be inserted into a key slot  134  (see FIG. 1) defined by the plug  130  to permit the plug  130  to be rotated about the axis  100  to move the hook-shaped cam  140  about the axis  100  between locked and unlocked positions wherein the cam  140  engages and disengages other suitably configured structure (not shown). To keep the plug  130  from rotating about the axis  100  when no suitably configured key is inserted into the key slot  134 , the plug  130  typically carries a plurality of tumblers (not shown) that are biased to extend radially outwardly into groove formations  136  (see FIGS. 4-7) defined by interior surface portions of the body  120 . When a suitably configured key is inserted into the key slot  134 , the key engages the tumblers causing them to withdraw from engagement with the groove formations  136  of the body  120 , which permits the plug  130  to rotate about the axis  100  when the key is turned. 
     Because interior body and plug details of cam locks that operate in the manner just described are quite well known in the art and are well understood by those who are skilled in the art, and because internal features of cam locks of this type form no part of the present invention, it is not necessary to include here a discussion of such details in order for effective use to be made of the present invention. Instead, reference is made to patents that disclose a variety of interior body and plug features of cam locks, switch locks, and the like, including U.S. Pat. Nos. 5,964,110, 5,799,520, 5,531,084, 5,485,735, 5,235,832, 5,111,007, 4,689,977, 4,633,689, 4,630,457 and other subject-matter related patents that are owned by The Eastern Company. 
     Referring to FIGS. 1-3, a shoulder  200  is defined by an enlarged diameter bezel  202  provided at a front end region of the body  120 . The shoulder  200  extends in a plane that is perpendicular to the axis  100  and faces rearwardly along the axis  100  for engaging a front side of a panel on which the body  120  is to be mounted. Although the shoulder  200  is depicted as being “continuous” in that it extends in an uninterrupted ring-like manner about the axis  100 , it will be understood that the shoulder  200  can be interrupted if there is a need for the shoulder  200  to be segmented or otherwise defined only in specific regions spaced about the axis  100 . In FIGS. 4,  5 ,  6  and  7  where the support panels  101 ,  102 ,  103 ,  104  are depicted, it will be seen that, when the body  120  extends through the mounting holes  111 ,  112 ,  113 ,  114  of the support panels  101 ,  102 ,  103 ,  104 , respectively, to support the cam lock  110  in its installed position, the shoulder  200  engages the front faces of the panels  101 ,  102 ,  103 ,  104 . 
     Referring again to FIGS. 1-3, an insertion portion  125  of the body  120  extends rearwardly along the axis  100  from the shoulder  200 . Projecting from opposite sides of the insertion portion  125  (in directions, that generally extend away from the axis  100 ) are pairs of arm portions  242 ,  252 ,  262 . While the arm portions  242 ,  252 ,  262  normally extend radially away from the axis  100 , the arm portions  242 ,  252 ,  262  can be flexed to fold inwardly into recesses  244 ,  254 ,  264  that are defined by the insertion portion  125  of tire housing  120 . 
     Referring to FIG. 2, engagement surfaces  240 ,  250  are defined by arm portions  242 ,  252 , respectively; and, engagement surfaces  260 ,  270  are defined by sizable tooth-like formations of arm portions  262 . The engagement surfaces  240 ,  250 ,  260 ,  270  face forwardly along the axis  100  toward the shoulder  200  and are configured to engage the rear faces of support panels of a variety of thicknesses when the front faces thereof are engaged by the shoulder  200 . In FIGS. 4,  5 ,  6  and  7  where the body  120  is shown in its installed position (i.e., the body  120  is shown mounted on the panels  101 ,  102 ,  103 ,  104  which are of differing thickness), it will be seen that the engagement surfaces  240 ,  250 ,  260 ,  270  face toward and engage rear faces of the panels  101 ,  102 ,  103 ,  104 , respectively. 
     The engagement surfaces  240  are defined by arm portions  242  of the body  120  that extend in a common plane which is indicated in FIG. 3 by the line  4 — 4 ; and the recesses  244  extend in this same plane. The engagement surfaces  250  are defined by arm portions  252  of the body  120  that extend in a common plane which is indicated in FIG. 3 by the line  5 — 5 ; and the recesses  254  extend in this same plane. The engagement surfaces  260 ,  270  are defined by arm portions  262  of the body  120  that extend in a common plane which is indicated by the line  6 — 6 ; and the recesses  264  extend in this same plane. As is best seen in FIGS. 3 and 4, the arm portions  242  are of substantially identical thickness (FIG.  3 ); are of substantially identical cross-section (FIG.  4 ); and have outwardly facing surfaces  241  that extend rearwardly from the engagement surfaces  240  (FIG.  4 ). As is best seen in FIGS. 3 and 5, the arm portions  252  are of substantially identical thickness (FIG.  3 ); are of substantially identical cross-section (FIG.  5 ); and have outwardly facing surfaces  251  that extend rearwardly from the engagement surfaces  250  (FIG.  5 ). As is best seen in FIGS. 3,  6  and  7 , the arm portions  262  are of substantially identical thickness (FIG.  3 ); are of substantially identical cross-section (FIGS.  6  and  7 ); have outwardly facing surfaces  261  that extend rearwardly from the engagement surfaces  260  (FIGS.  6  and  7 ); and have outwardly facing surfaces  265  that extend rearwardly from the engagement surfaces  270  to the engagement surfaces  260 . 
     Referring to FIG. 3, it will be seen that the planes identified by the lines  4 — 4  and  6 — 6  intersect the insertion portion  125  of the body  120  near where opposed flat side surfaces  127  intersect with opposed curved surfaces  129  of the insertion portion  125  of the body  120 . In essence, the planes identified by the lines  4 — 4  and  6 — 6  form an “X” that intersect at the center axis  100 . And, the plane identified by the line  5 — 5  extends perpendicular to the opposed flat surfaces  127 ; and, this same plane intersects the planes identified by the lines  4 — 4  and  6 — 6  at the center axis  100 . 
     Referring to FIG. 4, the arm portions  242  are connected by a thin cross-section of material  246  to the insertion portion  125  of the body  120 . Referring to FIG. 5, the arm portions  252  are connected by a thin cross-section of material  256  to the insertion portion  125  of the body  120 . Referring to FIGS. 6 and 7, the arm portions  262  are connected by a thin cross-section of material  266  to the insertion portion  125  of the body  120 . The thin cross-sections of material  246 ,  256 ,  266  are sufficiently thin that they can be flexed to permit the arm portions  242 ,  252 ,  262  to fold into the recesses  244 ,  254 ,  264  to the extent needed to permit the insertion portion  125  of the body  120  to pass through the holes  111 ,  112 ,  113 ,  114  of the support panels  101 ,  102 ,  103 ,  104  during installation of the body  120  on the panels  101 ,  102 ,  103 ,  104 . 
     If the body  120  is formed as by molding it from plastics material, the mold (not shown) is configured to form the arm portions  242 ,  252 ,  262  in their outwardly extended positions rather than folded inwardly into the recesses  244 ,  254 ,  264  so that the plastics material in the vicinities of the thin cross-sections  246 ,  256 ,  266  will take on the characteristic of “memory” that will cause the arm portions  242 ,  252 ,  262  to be biased toward their outwardly extended positions when the arm portions  242 ,  252 ,  262  are pressed inwardly into the recesses  244 ,  254 ,  264  as during insertion of the insertable body portion  125  through any of the mounting holes  111 ,  112 ,  113 ,  114  of the panels  101 ,  102 ,  103 ,  104 . 
     The support panel  102  depicted in FIG. 5 is the thickest of the four panels  101 ,  102 ,  103 ,  1 . 04 . The support panel  104  depicted in FIG. 7 is second-to-the-thickest of the four panels  101 ,  102 ,  103 ,  104 . The support panel  103  depicted in FIG. 6 is the third-thickest (or next-to-the-thinnest) of the four panels  101 ,  102 ,  103 ,  104 . The support panel  101  is the thinnest of the four panels  101 ,  102 ,  103 ,  104 . By way of example, these panel thicknesses can include four thicknesses selected from among 1.03 mm, 1.16 mm, 2.80 mm, 3.17 mm, 3.30 mm and 3.55 mm which comprise thicknesses that often are used in plastic guards for thermostats. If the arm portions  242  and  252  are provided with tooth formations (in the manner that the arm portions  262  are provided with tooth formations that define the engagement surfaces  260 ,  270 , respectively), all six of these common panel thicknesses can be accommodated by a single snap-in mount. 
     If the insertable body portion  125  is inserted through the mounting hole  112  of the support panel  102  (i.e., the thickest of the support panels  101 ,  102 ,  103 ,  104 ) to the installed position depicted in FIG. 5, only the arm portions  252  will “snap out” (i.e., move radially outwardly) when the body  120  reaches its installed position. This is because the engagement surfaces  240 ,  260 ,  270  are located closer to the shoulder  200  than are the engagement surfaces  250 , and are therefore remain confined within the hole  112  of the thickest support panel  102  when the arm portions  252  snap out to bring the engagement surfaces  250  into engagement with the rear face of the support panel  102 . Although the arm portions  242 ,  262  do not “snap out” to assist the arm portions  252  in performing a “retaining function” of preventing removal of the cam lock body  120  from the hole  112 , the fact that the arm portions  242 ,  262  are biased radially outwardly causes the outwardly facing surfaces  241 ,  261  of the arm portions  242 ,  262  to press outwardly to engage the material of the panel  102  that defines the hole  112  at four locations spaced circumferentially about the body  120  (with none of these locations residing within the plane indicated by the line  5 — 5  in FIG. 3 i.e., the plane within which the arm portions  252  move when they “snap outwardly” to the position shown in FIG. 5 where the arm portions  252  perform their retaining function) to perform what can be referred to as an “anti-rattle” function of eliminating “looseness” of the cam lock body  120  in the hole  112  and of minimizing the possibility that the body  120  will move relative to the panel  102  even under the influence of vibration. The engagement surfaces  250  that cooperate with the shoulder  200  to engage opposite sides of the panel  102  to perform the retaining function of the arm portions  252  are the engagement surfaces that are defined by the arm portions  252  which are stationed along the opposed flat side surfaces  127  of the insertion portion  125  of the body  120 . 
     If the insertable body portion  125  is inserted through the mounting hole  114  of the support panel  104  (i.e., the next-to-the-thickest of the support panels  101 ,  102 ,  103 ,  104 ) to the installed position depicted in FIG. 7, the arm portions  262  will “snap out” (after the arm portions  252  have “snapped out”) during the insertion of the insertion portion  125  of the body  120  through the hole  114  to move the body  120  to its installed position where the engagement surfaces  270  engage the rear face of the support panel  104 . However, as is seen in FIG. 7, the arm portions  242  will remain within the hole  114  and their outwardly-biased nature will cause their outwardly facing surfaces  241  to press radially outwardly (in the plane indicated by the line  4 — 4  in FIG. 3) against the material that defines the hole  114  to aid the arm portions  262  (which also are biased radially outwardly such that their outwardly facing surfaces  265  are caused to engage, as depicted in FIG. 7, and thus to press radially outwardly against the material of the panel  104  that defines the hole  114 —with the engagement of the arm portions  262  with the material that defines the hole  114  taking place within the plane indicated by the line  6 — 6  in FIG.  3 —a plane that is distinctly different from the plane  4 — 4  within which the outwardly facing surfaces  241  of the arm portions  242  engage the material of the panel  104  that defines the hole  114 ) in performing the “anti-rattle” function of minimizing looseness of the body  120  in the hole  114  and of preventing unwanted movement of the body  120  relative to the support panel  104  (thus, the arm portions  242  and  262  which extend in separate radially extending planes perform an anti-rattle function while the arm portions  262  which have snapped radially outwardly to bring their engagement surfaces  270  into engagement with the rear face of the panel  104  also perform a retaining function to ensure that the lock body  120  is held securely in place in the hole  114  of the panel  104 ). 
     If the insertable body portion  125  is inserted through the mounting hole  113  of the next-to-the-thinnest panel  103  to the installed position shown in FIG. 6, the arm portions  262  will “snap out” twice after the arm portions  252  have “snapped out” during the insertion of the insertion portion  125  of the body  120  through the hole  113  to move the body  120  to its installed position where the engagement surfaces  260  engage the rear face of the support panel  103 . However, as is seen in FIG. 6, the arm portions  242  will remain within the hole  113  and their outwardly-biased nature will cause their outwardly facing surfaces  241  to press radially outwardly (acting in the radially extending plane indicated by the line  4 — 4  in FIG. 3) against the material that defines the hole  113 ) while the the arm portions  262  function in the separate and distinct plane indicated by the line  6 — 6  in FIG. 3 to prevent unwanted movement of the body  120  relative to the support panel  103 . 
     If the insertable body portion  125  is inserted through tile mounting hole  111  of the thinnest panel  101  to the installed position shown in FIG. 4, the arm portions  242  will “snap out” after the arm portions  252  have “snapped out” once and after the arm portions  262  have “snapped out” twice during the insertion of the insertion portion  125  of the body  120  through the hole  111  of the thinnest panel  101  to its installed position where the engagement surfaces  240  engage tile rear face of the support panel  101 . 
     While the body  120  is not intended to be easily removed from panels on which it is installed, pressing all of the arm portions  242 ,  252 ,  262  radially inwardly into their recesses  244 ,  254 ,  264  can be accomplished with ease by pushing a ring-like member (not shown) over the insertion portion  125 —a ring-like member having an inner diameter that fits closely enough about the outer diameter of the insertion portion  125  to compress the arm portions  242 ,  252 ,  262  sufficiently to permit them to pass back through one of the holes  111 ,  112 ,  113 ,  114 . 
     Although the invention has been described in its preferred form with a certain degree of particularity, it is understood that the present disclosure of the preferred form has been made only by way of example, and that numerous changes in the details of construction and the arrangement of elements can be made without departing from the spirit and scope of the invention as claimed.