Abstract:
An electric circuit member in a housing has lead wires which protrude out an end of the housing. A portion of the housing is provided with external threading for mounting and dismounting of the whole assembly. In order to prevent twisting of the wires as assembly is mounted and dismounted, the assembly may be manipulated to let the electric circuit member and its lead wires slip relative to the threaded housing portion. Three variations are shown.

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates, in general, to a mounting assembly for releasably mounting an electric circuit element, and particularly, to a mounting assembly for connecting and disconnecting an electric circuit element relative to an article free from fear that the lead wires which extend from the electric circuit element will be twisted during the connecting and disconnecting operation. 
     In mounting a conventional electric circuit element including a housing and an electric circuit member such as a detecting device for chemical and/or physical analytical use, the electric circuit member is fixedly mounted within a housing. FIG. 1 shows an example of a conventional construction of such electric circuit element. Referring to FIG. 1, there are shown a housing 11 having a threaded portion 11a at its outer circumference, an electric circuit board 12 which is, for instance, of a type with a detecting circuit printed on a base plate, a screw 13 for securing the electric circuit board 12 onto the housing 11, lead wires 14 from the electric circuit board 12 for picking up electric signals from the electric circuit board 12 and for supplying the circuit board 12 with electricity, an outlet opening with an insulating bushing 15 for passing the lead wires therethrough, and a signal indicator 16 adapted to indicate by electric signals from the circuit member 12 or an electric computer element for logic operations. In this example, the electric circuit board 12 and the housing 11 are secured together by using appropriate means such as a screw 13 or an adhesive (not shown. When threadably connecting or disconnecting a detecting element or detector assembly 21 including the above mentioned circuit board 12 through a threaded hole provided in a cover plate 20 of a structure to be mounted with this detecting assembly as shown in FIG. 2, it is generally required to manually turn the detector assembly 21 with respect to the cover plate 20 in the directions shown by arrows 22 in FIG. 1. 
     During such connecting or disconnecting work, the housing 11 of the electric element 21 is caused to be manually rotated, thus resulting in an inevitable rotating motion of the electric circuit board 12 fixedly mounted thereon. Consequently, the lead wires 14 connected to the circuit board 12 are caused to be rotated or twisted in correspondence with a rotating motion of the above-mentioned housing 11. From each construction, there is a possibility of disconnection or short circuiting of the lead wires 14 due to breakage of the insulating material of the wires 14. 
     The present invention is essentially directed toward elimination of such drawbacks stated above as encountered in the conventional device. 
     SUMMARY OF THE INVENTION 
     It is therefore a primary object of the present invention to provide an improved mounting assembly for an electric circuit element wherein any possible twisting of the lead wires can effectively be prevented from occurring during the work of mounting or dismounting such electric circuit element to and from a member to which such element is to be mounted and dismounted. 
     It is another object of the invention to provide an improved mounting assembly for an electric circuit element whereby an electric circuit element can easily yet assuredly be connected and disconnected into and out of a structure for mounting and dismounting such element without the lead wires thereof being turned or twisted during such connecting and disconnecting work. 
     According to the present invention, briefly summarized by way of perferred embodiments thereof, for attaining those objects as well as other objects and advantages, there is provided an improved mounting assembly which includes an electric circuit member disposed in a housing and which has lead wires which protrude out an end of the housing. A portion of the housing is provided with external threading for mounting and dismounting of the whole assembly. In order to prevent twisting of the wires as the assembly is mounted and dismounted, the assembly may be manipulated to let the electric circuit member and its lead wires slip relative to the threaded housing portion. 
    
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING 
     The construction, principle, and details of the present invention, as well as further advantages thereof, will become more apparent from the following detailed description with respect to the preferred embodiments of the present invention, when read in conjunction with the accompanying drawings. 
     In the drawings; 
     FIG. 1 is a schematic view, partly in section, showing the interior construction of a detecting element including a conventional electric circuit member mounting assembly; 
     FIG. 2 is a schematic view, partly in section showing, for explanatory purposes, operation of a conventional arrangement shown in FIG. 1; 
     FIG. 3 is an elevational view showing the exterior of a first embodiment of the mounting assembly according to this invention; 
     FIG. 4 is a longitudinal sectional view, showing the interior construction of the mounting assembly of this invention shown in FIG. 3; 
     FIG. 5 is a fragmentary longitudinal sectional view, showing for explanatory purpose the interior mounting relationship of the mounting assembly of this invention. 
     FIG. 6(A) and FIG. 6(B) are views, showing for explanatory purposes the interior mounting relationship of a second embodiment of this invention; 
     FIG. 7 is an elevational view showing the exterior of a third embodiment of the invention; 
     FIG. 8 is a longitudinal sectional view, showing the interior construction of the third embodiment of the mounting assembly shown in FIG. 7; and 
     FIG. 9 is a fragmentary longitudinal sectional view, showing for explanatory purposes the interior mounting relationship of the mounting assembly shown in FIG. 7. 
    
    
     DETAILED DESCRIPTION 
     Description will now be given in detail on a preferred embodiment of a mounting assembly for use in mounting an electric circuit element according to the present invention by referring to the accompanying drawings. 
     Referring to FIGS. 3 and 4, there is shown a first embodiment of the present invention. 
     In FIG. 3, there is shown an elevational view showing the exterior of a mounting assembly of the invention for use in a detector assembly for detecting the quanity or liquid level and specific gravity of an electrolyte for an electric battery. In this Figure, there is shown a housing 31 constituting an outside fixing member of the mounting assembly, the housing 31 being provided at its outer periphery with a threaded portion 31a adapted to threadedly connect the mounting assembly onto a structure for mounting the detector assembly thereon, and also provided with a knurled portion 31b for preventing possible slipping when manually turning the mounting assembly. Also shown are a float 32 adapted to move with buoyancy upwardly or downwardly according to a change in the quantity or liquid level and specific gravity of the electrolyte of an electric battery, a rubber cap 33 with a resilient property, adapted to fix the electric circuit board to the housing, and a pair of lead wires 34. FIG. 4 is an elevational view, in vertical section, showing the interior construction of the detector assembly, in which like parts are designated by like reference numerals. In FIG. 4, there is shown an electric circuit member 35 which has an electric detecting circuit printed on a base plate, which is placed in mechanical contact with the rubber cap 33 at a shoulder surface 401 on one hand and with the housing 31 at a shoulder surface 402 on the other hand. 
     Description is now given of the operation of the mounting assembly of the construction mentioned above, wherein a mounting assembly of this invention including therein a detector assembly which is installed on a mount on a cover plate 51 of an electric battery as shown in FIG. 5. When dismantling the mounting assembly from the mount on the cover plate, the rubber cap 33 is first held by one hand 52, so as not to permit its rotation, while the housing 31 is manually rotated by the other hand. As best seen in FIG. 4, considering that both of the two shoulder surfaces 401 and 402 are disposed between the electric circuit 35 and other parts, and the shoulder surface 401 is in contact with a cap made of a resilient material such as rubber, it is apparent that the shoulder surface 401 encounters much greater friction force than that at the shoulder surface 402. For this reason, even though the housing 31 is caused to be rotated manually, the circuit member 35 is prevented from such rotating motion. In other words, it is practical to remove or dismantle the detector assembly from its mount leaving the lead wires 34 free from any distortion or twisting during this dismantling operation. Likewise, this is also true with the case of installing the detector assembly onto its mount. 
     Referring now to FIGS. 6(A) and (B), there is shown another embodiment of this invention. In this embodiment, there are provided a rigid cap and resilient means such as a coil spring which function, as a resilient member in place of the rubber cap as illustrated in FIGS. 3 and 4. In FIG. 6(A), the electric circuit member 35 is fixedly disposed between the housing 31 and the cap 33a by use of a coil spring 601. When dismantling the detector assembly from its mount, firstly the cap 33a is manually pushed in the direction as shown by an arrow in FIG. 6(B), thus relieving the frictional force acting between the cap 33a and the housing 31, and therefore, preventing the cap 33a from being rotated in correspondence with the rotation of the housing 31 when it is manually rotated. Consequently, the electric circuit 35 is prevented from being rotated as it is held by the spring 601, thus assuring that the lead wires 34 are not twisted during the work of dismantling the detector assembly from its mount. 
     According to the embodiments of the present invention as described hereinbefore, there is provided an improved arrangement wherein there is interposed a resilient means such as a rubber cap, or combination of a rigid cap and a coil spring between the electric circuit and the housing, whereby in a detector assembly including an electric circuit, the electric circuit member is fixedly mounted by the resilient member. When installing and dismantling this detector assembly on and from its mount, only the housing or the outside fixing member of the assembly is manually rotated while leaving the electric circuit member unturned. With such construction, there is produced an advantageous feature that the lead wires are assuredly prevented from disconnection and/or short circuiting due to breakage of the insulating material therearound usually caused in conventional mounting assemblies by twisting of the lead wires during installation and dismantling work of the detector assembly onto and out of its mount. This advantage is attained by virtue of the construction such that the detector assembly can be installed and dismantled without any fear of twisting the lead wires. 
     Referring now to FIGS. 7, 8 and 9, there is shown a third embodiment of the present invention. 
     FIG. 7 is an elevational view showing the exterior of a coupling device of this invention for use in a detector assembly which is designed for detecting the quantity or liquid level and the specific gravity of the electrolyte in an electric battery. In this Figure, there are shown a housing 131 comprising an electric circuit element, and a housing guide 132 constituted by an outside fixing member formed thereon with a knurled portion for preventing occasional slipping during a manual turning operation. The housing 131 is inserted with a loose fit into the housing guide 132 so that these members are freely movable with respect to each other. On the other hand, the housing guide 132 is provided with a threaded portion 132a for threaded connection to the mount on the battery, and also with a slit 132b so that the diameter of the housing guide may be slightly reduced at its threaded portion when the housing guide is screwed down into the threaded opening of the cover plate. Thus, the housing 131 may be positively held and tightly secured in the mounted position. Also shown is a float 133, which is adapted to move upwardly or downwardly with its buoyancy following the change in the liquid level and the specific gravity of the electrolyte of a battery. 33b  is a rubber cap for securing the electric circuit part to the housing 131, and also for sealing the circuit part from the outside. There is shown a pair of lead wires 34. The housing 131, the float 133 and the like are generally made of a plastic of acid-resistant characteristic. 
     FIG. 8 is a schematic view showing the interior construction of the detector assembly, in which there is shown a housing guide 132 made of a plastic or the like, having a construction such that the housing 131 is prevented from coming out of the housing guide 132 by means of a contact surface 401b having a shouldered portion 401a at the end of the inner circumference of the housing guide. When installing or dismantling the detector assembly onto or out if its mount, it is required to manually turn only the housing guide 132 on the contact surface 401b. Also shown is an electric circuit member 136 for detecting the travel of the above mentioned float 133, which circuit member is of a type wherein there is provided an electric circuit printed on a base plate, and which includes a sensor 136a comprising a coil or a reed switch, the detecting signal being input through the lead wires 34 to a signal processing station such as an electric computer 16 as illustrated in FIG. 1. 
     It should be noted, in the embodiment having the construction as illustrated in FIGS. 7 and 8, that the housing 131 and the electric circuit 136 provided within the housing 131 constitute the electric circuit element, and the housing guide 132 constitutes the outside fixing member. Consequently, when mounting and dismantling the above mentioned electric circuit element onto and out of its mount, the housing 131 which constitutes an essential component of the electric circuit element is not turned. 
     Description is now given of the operation of the third embodiment of this invention having the construction described above. As shown in FIG. 9, when the detector assembly is installed or dismantled on or from the cover plate 51 of a battery, firstly the housing 131 is held by gripping the rubber cap 33b with one hand, while manually rotating the housing guide 132 with the other hand. Then, since the housing guide 132 is caused to be held and fixedly secured by means of the above mentioned slit 132b shown in FIG. 7, the housing 131 is likely to rotate unless it is held by hand, however, when the housing is loosened to some extent, the constricted slit opening reverts to its original spacing thus releasing the tightening force with which the housing guide 132 holds the housing 131, and therefore, the housing guide 132 and the housing 131 are now movable freely relative to each other. Consequently, there exists no longer a mechanical connection between the housing guide 132 and the housing 131, thus leaving the housing 131 to be free from the rotating motion of the housing guide 132. In other words, the detector assembly can be removed from its mount with the lead wires 34 being free from twisting during the dismantling operation. It is also apparent that this is true with a mounting operation. 
     As fully described hereinbefore, in this third embodiment of this invention where the electric element of the detector assembly or the like comprises the lead wires, there is provided a meritorious effect such that the housing guide only can be manually rotated leaving the housing to be free from the rotating motion of the housing guide when installing and dismantling the electric element. This is owing to such duplex construction that the housing guide and the housing engage with each other with a loose fit unless tightened by the screw threads so that there is permitted smooth rotational movement between the two, thus preventing the lead wires stemming from the electric element from being twisted during the installation and dismantling operation, consequently there is no longer a risk of disconnection of the lead wires and/or short circuit due to breakage of the insulating material of the lead wires caused by twisting of such wires during installation and dismantling work of the assembly. 
     Although detailed description has been made exclusively on the foregoing typical embodiments of this invention, it should be understood that the preferred embodiments of the invention as described and shown herein do not mean in any way limitation of this invention to such embodiments, but on the contrary, many changes, variations and modifications with respect to the construction and arrangement in practice thereof can further be derived by those skilled in the art to which the present invention pertains, whereby the advantageous features of this invention may be realized without departing from the spirit and scope of the invention as set forth in the appended claims.