Abstract:
A retainer includes: a connecting piece; one or more retaining parts provided at either end of the connecting piece and having a hole into which a terminal of an electrical component fits; an arm piece extending from near the hole; and a washer that is formed on the fore-end of the arm piece and is for fitting together with the hole over the terminal, wherein the connecting piece, the retaining part, the arm piece, and the washer are formed integrally of an insulating material having good expansion/contraction properties.

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to retainers for retraining terminals on a high-pressure part of a lamp, and strobe devices using the retainers. 
   2. Description of Related Art 
     FIG. 7  is an oblique view of a strobe device  1  suitable for installation in cameras, and  FIG. 6  is an exploded oblique view thereof. The strobe device  1  includes a case  2  made of a resin, a reflector  3  made of a metal, and a rod-shaped lamp  4 . The case  2  has a front opening  21 . The reflector  3  has a front opening  31  and fits into the case  2  through the opening  21  of the case  2 . The lamp  4  is arranged inside the reflector  3 . The lamp  4  has terminals  41  and  41   a  on opposite ends thereof, which project outwardly through holes  23 ,  33  and  33 ,  23 , formed at opposite ends of the case  2  and the reflector  3 . 
   The lamp  4  is fixed to the case  2  with a band-shaped retainer  5  that has good expansion/contraction properties and insulation performance. (See, for example, Japanese Unexamined Pat. App. Pub. No. 9-113969). 
   The retainer  5  has holes  53  and  53   a , which are formed at opposite ends of an elongated connecting piece  51  and into which terminals  41  and  41   a  are fitted tightly. In order to fix the lamp  4  to the case  2  with the retainer  5 , one hole  53  is fitted onto the terminal  41  on one end of the lamp  4 , the connecting piece  51  is stretched along the outer rear face of the case  2 , and the other hole  53   a  is fitted onto the terminal  41   a  on the other end of the lamp  4 . The pulling force of the retainer  5  tending to return to its original shape presses the lamp  4  against the rear of the case  2 , thus fastening the lamp  4  to the case  2 . (See  FIG. 7 .) As shown in  FIG. 8 , conductor wires  6  are soldered onto the terminals  41  and  41   a.    
   The holes  53  and  53   a  of the retainer  5  are fitted tightly onto the terminals  41  and  41   a . The fore-end of the retainer  5  electrically insulate the solder  7  from the reflector  3 , thus preventing electric leakage. 
   As shown in  FIG. 8 , however, a pulling force acts on both ends of the retainer  5  in a state in which the lamp  4  is fitted. As a result, the hole  53  of the retainer  5  is elongated in the stretching direction, producing a gap  50  between the hole  53  and the terminal  41  of the lamp  4 . 
   Due to the just-noted gap  50 , the retainer often loses the effects of electrical insulation and electric leakage prevention, leading to such problems as giving electrical shocks to users and causing flashing failures. 
   It is an object of the present invention to provide a terminal retainer free from such problems as giving electrical shocks to users and flashing failures. 
   BRIEF SUMMARY OF THE INVENTION 
   A retainer  5  includes: a connecting piece  51 ; one or more retaining parts  52  provided on either end of the connecting piece  51  and having a hole  53  into which a terminal  41  of an electrical component fits; an arm piece  54  extending from near the hole  53 ; and an washer  55  formed on a fore-end of the arm piece  54  and for fitting together with the hole  53  over the terminal  41 . All of the connecting piece  51 , the retaining part  52 , the arm piece  54 , and the washer  55  are integrally formed of an insulating material having good expansion/contraction properties. 
   By folding backward the arm piece  54  of the retainer  5  and fitting the washer  55  over the terminal  41  of the electrical component, the washer  55  can serve the role of electrical insulation and electric leakage prevention. 
   Even when the connecting piece  51  is stretched, the force from the connecting piece  51  does not directly act on the arm piece  54  provided with the washer  55 , and therefore, no pulling force acts on the washer  55 . Consequently, deformation of the hole  58  of the washer  55  is prevented. 
   Thus, the retaining force between the connecting piece  51  and the terminal  41  of the electric component does not cause adverse effects, and it is possible to prevent loss of electrical insulation performance and electric leakage prevention effect. 
   Since the washer  55  is formed integrally with the retainer  5 , loss of the washer  55  or dropping of the washer  55  is not likely to happen when fitting the washer  55  onto the terminal  41 . Thereby, assembling workability is also improved. Because the washer  55  can be formed integrally with the connecting piece  51 , manufacturing cost can be reduced in comparison with the case in which the washer is independently produced. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is an exploded oblique view of a strobe device; 
       FIG. 2  is an oblique view of a retainer; 
       FIG. 3  is an oblique view illustrating a primary portion of the strobe device showing how a lamp is fitted thereto; 
       FIG. 4  is a front view of a retainer according to another embodiment; 
       FIG. 5  is a cross-sectional view showing how a lamp is fitted using the retainer of  FIG. 4 ; 
       FIG. 6  is an exploded oblique view of a conventional strobe device; 
       FIG. 7  is an oblique view of the conventional strobe device; and 
       FIG. 8  is an oblique view showing how a conventional lamp is fitted with the conventional example. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   First Embodiment 
     FIG. 1  is an exploded view of a strobe device  1  for digital cameras. 
   The strobe device  1  comprises a horizontally oblong case  2  made of a synthetic resin, a horizontally oblong reflector  3  made of a metal, a rod-shaped lamp  4  arranged inside the reflector  3 , and a retainer  5  for fixing the lamp  4  to the case  2 . The case  2  is held inside a camera body (not shown). The reflector  3  is accommodated into the case  2  through a front opening  21  of the case  2 . The lamp  4  of the present embodiment is a xenon tube. 
   Side walls  22 ,  22  of the case  2  have holes  23 ,  23  formed near the rear, and side plates  32 ,  32  of the reflector  3  also have holes  33 ,  33  formed near the rear. 
   Terminals  41  and  41   a  on opposite ends of the lamp  4  project outward of the case  2  through the holes  23 ,  33  and  33 ,  23 , respectively, with a slight clearance therebetween. 
   The retainer  5  is formed of a material that has excellent insulation performance and good expansion/contraction properties and does not dissolve even when in contact with melted solder, such as silicone rubber. 
   As illustrated in  FIG. 2 , the retainer  5  is provided with retaining parts  52  and  52   a  on opposite ends of a band-shaped connecting piece  51 , and arm pieces  54 ,  54  projecting from the retaining parts  52  and  52   a  so as to be substantially perpendicular to the connecting piece  51 . The fore-ends of the arm pieces  54 ,  54  are furnished with washers  55  and  55   a.    
   Holes  53  and  53   a  into which the terminals  41 ,  41   a  of the lamp  4  fit tightly are formed at the center portion of the retaining parts  52  and  52   a . The terminals  41  and  41   a  also fit tightly into holes  58 ,  58  formed at the center of the washers  55  and  55   a.    
   The distance between the holes  53  and  53   a  of the retaining parts  52 ,  52  is shorter than the distance between the terminals  41  and  41   a  of the lamp  4 . To attach the retainer  5  onto the lamp  4 , the retainer  5  is stretched as will be described later so that connecting piece  51  is put on the outer rear face of the case  2 , and the terminals  41  and  41   a  of the lamp  4  are fitted into the holes  53  and  53   a.    
   An arc-shaped wall  56  is formed protruding from the outer periphery of each of the washers  55  and  55   a  of the retainer  5 . The terminals  41  and  41   a  of the lamp  4  are insulated from other components in the vicinity of the terminals  41  and  41   a  by the arc-shaped walls  56  in a state in which the strobe device  1  is mounted to a camera. 
   Installation of Retainer 
   First, the reflector  3  is inserted through the opening  21  of the case  2  so that the rear face of the reflector  3  is put against the rear wall  24  of the case  2 . 
   The lamp  4  is inserted into the case  2  and the reflector  3 . The terminals  41  and  41   a  on the opposite ends of the lamp  4  are stuck outward of the case  2  through the holes  23 ,  33  and  33 ,  23  in the opposite end portions of the case  2  and the reflector  3 . 
   Next, the connecting piece  51  of the retainer  5  is stretched so as to put against the outer rear face of the case  2 . The terminal  41  on one end of the lamp  4  is fitted into the hole  53  of the retaining part  52  on one end, and the terminal  41   a  on the other end of the lamp  4  is fitted into the hole is fitted to the hole  53   a  of the retaining part  52   a  on the other end. The lamp  4  is pressed toward the rear wall  24  of the case  2  by the pulling force of the connecting piece  51  tending to return to its original shape. Thus, the lamp  4  and the reflector  3  can be retained. 
   The retaining part  52   a  serves as a mount part  57   a  for mounting the retainer  5  onto the case  2  with respect the retaining part  52  of the retainer  5  that has been fitted onto the one terminal  41 . Likewise, the retaining part  52  also serves as a mount part  57  for mounting the retainer  5  onto the case  2  with respect to the retaining part  52   a  of the retainer  5  that has been fitted onto the other terminal  41   a.    
   That is, both retaining parts  52  and  52   a  also serve as the mount parts  57  and  57   a  for mounting the lamp  4  to the case  2 . 
   As illustrated in  FIG. 3 , the arm pieces  54 ,  54  are folded backward from near the opposite ends of the retainer  5  so that the terminals  41  and  41   a  of the lamp  4  are fitted tightly into the holes  58 ,  58  of the washers  55  and  55   a.    
   Conductor wires  6  are attached onto each of the terminals  41  and  41   a  by solder  7  within each of the arc-shaped walls  56  on the washers  55  and  55   a.    
   Since the washers  55  and  55   a  are not located on the connecting piece  51 , the washers  55  and  55   a  do not receive a pulling force even when the connecting piece  51  is stretched. For this reason, the holes  58 ,  58  of the washers  55  and  55   a  do not deform in such a manner that gaps are between the washers and the terminals  41  and  41   a . Thus, the washers  55  reliably serves the role of electrical insulation and electric leakage prevention. 
   Since the washers  55  and  55   a  are formed integrally with the retainer  5 , loss of the washers  55  and  55   a  or dropping of the washers  55  and  55   a  is not likely to happen when fitting the washers  55  and  55   a  onto the terminals  41  and  41   a . As a consequence, assembling workability is improved. 
   Due to the fact that the washer  55  can be formed integrally with other parts by die forming, manufacturing cost can be reduced in comparison with the case in which the washers are independently produced. 
   It should be noted that in the just-described embodiment, the arm pieces  54 ,  54  of the retainer  5  extend from the retaining parts  52  and  52   a  so as to be perpendicular to the connecting piece  51 . The purpose is to prevent the arm pieces  54  that have been folded backward from making contact with the case  2  or other components near the strobe device  1 . 
   The orientation of the arm pieces  54 ,  54  with respect to the connecting piece  51  is not limited as long as they do not interfere with the case  2  or other components. 
   It is desirable that the length of each arm piece  54  be as short as possible as long as it is possible to fold the arm piece  54  backward so that the washers  55  and  55   a  can be fitted onto the terminals  41  and  41   a.    
   Second Embodiment 
     FIG. 4  illustrates a retainer  5  according to another embodiment, and  FIG. 5  illustrates how the retainer  5  is used for an automobile headlight mount part. 
   The retainer  5  has a retaining part  52  at the center. From the retaining part  52 , connecting pieces  51 ,  51  extend toward both right and left sides. The fore-ends of the connecting piece  51 ,  51  have mount parts  57 ,  57 . Each of the mount parts  57  are formed so that it has a hole  59  formed at the fore-end of the connecting piece  51 . 
   An arm piece  54  extends from the retaining part  52 , and a washer  55  is formed on the fore-end of the arm piece  54 . 
   As shown in  FIG. 5 , a lamp  8  is fitted into a hole  71  of a lamp mount seat  70  of the headlight, and a flange  81  of the lamp  8  is attached onto the mount seat  70 . A terminal  91  of a plug  9 , which is arranged rearward of the lamp  8  and is isolated from the lamp, is fitted into the hole  53  of the retaining part  52  of the retainer  5 . The connecting pieces  51 ,  51  of the retainer  5  are stretched and hooks  73 ,  73  are fitted into the holes  59 ,  59  of both mount parts  57 ,  57 . 
   By the pulling force of the connecting pieces  51 ,  51 , the plug  9  is pressed against a terminal face  82  of the lamp  8 . 
   The arm piece  54  of the retainer  5  is folded backward to fit the hole  58  of the washer  55  tightly onto the plug  9 . A conductor wire  6  is connected to the plug  9  with solder  7 . 
   The washer  55  serves the role of electrical insulation and electric leakage prevention, as in the foregoing embodiment. 
   Only selected embodiments have been chosen to illustrate the present invention. To those skilled in the art, however, it will be apparent from the foregoing disclosure that various changes and modifications can be made herein without departing from the scope of the invention as defined in the appended claims. Furthermore, the foregoing description of the embodiments according to the present invention is provided for illustration only, and not for limiting the invention as defined by the appended claims and their equivalents.