Abstract:
A locking apparatus for a movable carry module, comprises a controller using to fix the movable carry module of an electric device. The controller has a movable locking shaft normality stretch in the movable carry module, and applies to fix the movable carry module. The electric device supplies the electric power to the controller when receiving the external electric power, and then the locking shaft departs from the movable carry module, such that the movable carry module can move freely.

Description:
FIELD OF THE INVENTION 
     The present invention relates to a locking apparatus adopted for use on an electric device such as scanner, multi-function peripheral (MFP) and the like, and particularly to latch an optical module of a scanner to prevent scanning operation before the latch condition is released. 
     BACKGROUND OF THE INVENTION 
     In the digital technology area, the development of photoelectric technology has spawned many different electric devices such as scanners, digital cameras, digital video cameras, and the like. The scanner can rapidly transform paper documents to electronic files, hence is widely used in paperless office environments. 
     A conventional scanner includes at least a case, a lid, an optical module and a transmission mechanism. The case has a scan window. The lid is pivotally coupled on one side of the case in a movable manner. The optical module and the transmission mechanism are located in the case. The optical module is mounted onto a carrier. The transmission mechanism is coupled with the carrier for moving the optical module to and reciprocally within the range of the scan window. Because the optical module determines the quality of the scanning result of the scanner, and the optical module is a movable mechanism, to prevent the optical module from undue vibration during transportation or carrying, resulting in focus error or damage, scanner manufacturers usually include a latch coupler on the carrier of the optical module. Before the scanner is shipped from the plant, the carrier is anchored by the latch coupler, to prevent the optical module from being damaged during transportation or carrying. Users have to remove the latch coupler before use at the first time, otherwise the scanner cannot perform a scanning operation. 
     Although scanner manufacturers have clearly marked or noted to remind users to remove the latch coupler before use, many users still neglect this procedure. They could start the scanner without removing the latch coupler. As a result, the transmission mechanism or the optical module could be damaged. 
     To remedy this problem, some vendors have installed the latch coupler on the case close to the connection port. When the latch coupler latches the carrier, it also covers the connection port, so that users have to remove the latch coupler to connect the flat cable or power cord to the connection port. This scheme can prevent users from starting the scanner before the latch coupler has been removed. However, such a design aims to prevent damages during transportation for vendors and the mistaken first time operation of users. When users move the scanner themselves after first installation, they do not always remember to latch the latch coupler again, or try to omit this step to save the trouble of removing and reconnecting the connection line. Hence this is not a desirable design. 
     SUMMARY OF THE INVENTION 
     In view of the foregoing concerns, the present invention aims to provide a locking apparatus for a movable carry module that can automatically restrict the motion of the carry module according to the power supply condition of the electric device, so that electronic elements such as the optical module on the carry module may be prevented from being damaged. 
     The locking apparatus according to the invention mainly includes a controller, which has a locking shaft. The locking shaft is extended into the movable carry module to prohibit the movable module from moving. Namely, when the electric device is not in use or being transported, the movable carry module may be mounted securely on the electric device through the controller. When the electric device is in use, connecting to city power energizes it. The electric power is also transferred to the controller through the electric device to unlatch the locking shaft from the movable carry module, so that the movable module is moved as desired to perform scanning operation. 
     The foregoing, as well as additional objects, features and advantages of the invention will be more readily apparent from the following detailed description, which proceeds with reference to the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIGS. 1A and 1B  are schematic views of a first embodiment of the locking apparatus of the invention. 
         FIGS. 2A and 2B  are schematic views of the first embodiment of the invention in operating condition. 
         FIGS. 3A and 3B  are schematic views of a second embodiment of the locking apparatus of the invention. 
         FIGS. 4A and 4B  are schematic views of the second embodiment of the invention in operating condition. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The present invention aims to provide a locking apparatus for a movable carry module to be adopted for use on an electric device such as a scanner. While the following embodiments use the scanner as an example, it is not a limitation. Other electric devices that have a movable carry module, which requires to be latched to prevent moving during transportation or being damaged, and the latch, to be released before the electric device is operated, are within the covering scope of the present invention. 
     Referring to  FIGS. 1A and 1B , the locking apparatus according to the invention is adopted for use on an electric device such as a scanner  60 . The scanner  60  includes at least a guiding rod  40  and a movable carry module  30 . The movable carry module  30  carries an optical module (not shown in the drawings) which consists of electronic elements. The movable carry module  30  is driven by a transmission mechanism (not shown in the drawings) to move linearly and reciprocally on the guiding rod  40 . The optical module scans scanning objects such as documents. The image scanning technology is well developed and known in the art, and forms no part of the invention, thus this portion is omitted in the further discussion. 
     The locking apparatus according to the invention includes a controller  10 . The controller  10  has a movable-locking shaft  20 , which has a roller  21  at one end. The controller  10  is connected electrically to the scanner  60 , and is actuated by system power supply ‘ON’ and ‘OFF’ of the scanner  60  to control the moving condition of the locking shaft  20 . In addition, the movable carry module  30  has a cavity  31  corresponding to the locking shaft  20 . 
     In general, when an electric device such as a scanner  60  is not yet plugged in the power supply socket of city power, or the power supply socket is plugged but the power supply switch is OFF, the movable carry module  30  is at a preset idling position. The locking shaft  20  of the controller  10  is extended into the cavity  31  of the movable carry module  30  in normal condition, to restrict the moving range of the movable carry module  30 . Thereby, a electric device such as a scanner  60  may be prevented from impact of external forces during transportation and anchored securely to avoid damage The locking shaft  20  is coupled with a spring  90  which is compressed and provides a returning elastic force to push the locking shaft  20 , so that the locking shaft  20  does not escape the cavity  31  when the scanner  60  is shaken under external forces. Referring to  FIGS. 2A and 2B , when the power supply plug  70  of an electric device such as a scanner  60  is connected to the power supply socket  80  of the city power, or the power supply switch is ‘ON’, electric power is also supplied to the controller  10 . The locking shaft  20  is driven by the magnetic force generated by a solenoid valve (not shown in the drawings) in the controller  10  to compress the spring  90  and escapes the cavity  31 . Hence the movable carry module  30  is free from the harness of the locking shaft  20  and may be moved freely. The roller  21  on the locking shaft  20  makes the shaft  20  easier to move in and out of the cavity  31 . The solenoid valve in the controller  10  is a technique known in the art and forms no part of the invention, thus its details are omitted from further discussion. 
     The controller  10 , besides being located on an electric device such as a scanner  60 , may also be located on the movable carry module  30  to achieve the function of restricting the motion of the movable carry module  30 . Refer to  FIGS. 3A and 3B  for a second embodiment of the invention. In this embodiment, the controller  10  is located on the movable carry module  30 . When the power supply plug of the electric device such as the scanner  60  is not connected to the power supply socket of the city power, or the power supply socket is plugged but the power supply switch is OFF, the movable carry module  30  is at a preset idling position. The scanner  60  has an anchor member  50  corresponding to the controller  10 . The anchor member  50  has a trough  51  to receive the locking shaft  20 . The locking shaft  20  is pushed by the spring  90  to extend and insert into the trough  51  in normal condition, to restrict the moving range of the movable carry module  30 . Thereby, when an electric device such as a scanner  60  is not in use or from being transported, the movable carry module  30  may be secured without being damaged. 
     Referring to  FIGS. 4A and 4B , when the power supply plug  70  of the electric device such as the scanner  60  is connected to the power supply socket  80  of the city power, or the power supply switch is ON, electric power is also supplied to the controller  10 . The locking shaft  20  is driven by the magnetic force generated by a solenoid valve (not shown in the drawings) in the controller  10 , to overcome the compression force of the spring  90  and escape the trough  51 . Hence the movable carry module  30  is free from the harness of the locking shaft  20  and may be moved freely. The roller  21  on the locking shaft  20  makes the locking shaft  20  easier to move in and out of the trough  51 . 
     In summary, the locking apparatus according to the invention can move away the locking shaft  20  of the controller  10  to release the locking relationship with the movable carry module  30  while the system power supply of the scanner  60  is activated, so that the movable carry module  30  becomes movable freely. In addition, when the scanner  60  is not in use or during transportation, the locking shaft  20  can restrict the moving range of the movable carry module  30  and establish a locking relationship between the movable carry module  30  and the scanner  60 . 
     Based on the previous discussion, it is clear that the invention can automatically alter the operation of the controller through the system power supply condition. This is a user-friendly operation. Namely, when users switch the power supply ON or OFF, they can also control the latch condition of the movable carry module. This has a simpler structure and costs less. Thus it offers significant improvement of conventional techniques. 
     While the preferred embodiments of the invention have been set forth for the purpose of disclosure, modifications of the disclosed embodiments of the invention as well as other embodiments thereof may occur to those skilled in the art. Accordingly, the appended claims are intended to cover all embodiments, which do not depart from the spirit and scope of the invention.