Patent Publication Number: US-2022221034-A1

Title: Linear actuator and linear actuator assembling method

Description:
RELATED APPLICATIONS 
     This application claims priority to China Application Serial Number 202110030339.6, filed Jan. 11, 2021, which is herein incorporated by reference. 
     BACKGROUND 
     Technical Field 
     The present disclosure relates to a linear actuator and a linear actuator assembling method. More particularly, the present disclosure relates to a linear actuator having a threaded shaft and a linear actuator assembling method. 
     Description of Related Art 
     The most common linear actuator drives a threaded shaft to allow a driven object to move linearly relative to the linear actuator, which leads to a wide use in a lot of fields. A motor is usually adapted by the linear actuator to provide power, and different transmission elements can be employed to change the power transmitting conditions, e.g., the direction and the output ratio, based on demands. The linear actuator can further include controllers for detecting or adjusting the power output, and the complex elements lead to difficulty for assembling the linear actuator. 
     In addition, the scale of the threaded shaft is changed based on the demands, and the linear actuator is allowed to be assembled after the scale of the threaded shaft is confirmed; therefore, the manufacture efficiency is low. 
     Based on the above problems, how to increase the assembly efficiency and convenience of the linear actuator becomes a pursued target for practitioners. 
     SUMMARY 
     According to one aspect of the present disclosure, a linear actuator assembling method includes a semi-finished product assembling step and a threaded shaft assembling step. The semi-finished product assembling step is to form a semi-finished product, and the semi-finished product includes a case, a main gear, and a main gear bearing. The main gear and the main gear bearing are surrounded and restricted by the case, and the main gear bearing is sleeved on the main gear. In the threaded shaft assembling step, a threaded shaft is reversely assembled, and one end of the threaded shaft is inserted into the main gear to allow the end of the threaded shaft to be restricted by the main gear. 
     According to another aspect of the present disclosure, a linear actuator includes a semi-finished product and a threaded shaft. The semi-finished product includes a case, a driving module, and a transmission module. The case defines an inner space, and the driving module is disposed within the inner space and includes a motor. The transmission module is disposed within the inner space and includes a main gear driven by the motor and a main gear bearing sleeved on the main gear. One end of the threaded shaft is inserted into and restricted by the main gear. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The disclosure can be more fully understood by reading the following detailed description of the embodiments, with reference made to the accompanying drawings as follows: 
         FIG. 1  shows a three-dimensional schematic view of a linear actuator according to one embodiment of the present disclosure. 
         FIG. 2  shows one partial exploded view of the linear actuator of the embodiment of  FIG. 1 . 
         FIG. 3  shows another partial exploded view of the linear actuator of the embodiment of  FIG. 1 . 
         FIG. 4  shows a three-dimensional schematic view of an alignment of a distance adjusting module of the linear actuator of the embodiment of  FIG. 1 . 
         FIG. 5  shows a partial three-dimensional schematic view of the linear actuator of the embodiment of  FIG. 1 . 
         FIG. 6  shows a block diagram of a linear actuator assembling method according to another embodiment of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     It will be understood that when an element (or mechanism or module) is referred to as being “disposed on”, “connected to” or “coupled to” another element, it can be directly disposed on, connected or coupled to another element, or it can be indirectly disposed on, connected or coupled to another element, that is, intervening elements may be present. In contrast, when an element is referred to as being “directly disposed on”, “directly connected to” or “directly coupled to” another element, there are no intervening elements present. 
     In addition, the terms first, second, third, etc. are used herein to describe various elements or components, these elements or components should not be limited by these terms. Consequently, a first element or component discussed below could be termed a second element or component. 
       FIG. 1  shows a three-dimensional schematic view of a linear actuator  10  according to one embodiment of the present disclosure.  FIG. 2  shows one partial exploded view of the linear actuator  10  of the embodiment of  FIG. 1 .  FIG. 3  shows another partial exploded view of the linear actuator  10  of the embodiment of  FIG. 1 . Please refer to  FIGS. 1, 2 and 3 , the linear actuator  10  includes a semi-finished product  100  and a threaded shaft  200 . The semi-finished product  100  includes a case  110 , a driving module  120 , and a transmission module  130 . The case  110  defines an inner space, and the driving module  120  is disposed within the inner space and includes a motor  121 . The transmission module  130  is disposed within the inner space and includes a main gear  131  driven by the motor  121  and a main gear bearing  132  sleeved on the main gear  131 . One end of the threaded shaft  200  is inserted into and restricted by the main gear  131 . A bushing  180  can be sleeved on one side of the main gear  131 . When assembling the semi-finished product  100  and the threaded shaft  200 , the threaded shaft  200  can be inserted from the abovementioned side of the main gear  131  into the main gear  131  and then can be restricted thereby. The main gear bearing  132  is in association with the bushing  180  to allow the main gear  131  to rotate stably about one axis. In addition, the main gear  131  can further include an engaging hole  1311  having an inner thread (not shown) configured for the threaded shaft  200  to screw therewith, thereby linking the threaded shaft  200  and the main gear  131 . 
     Hence, because the semi-finished product  100  can be manufactured in advance, the threaded shaft  200  that is suitable for the demands can then be chosen and assembled, and the assembling efficiency and convenience of the linear actuator  10  can be increased. 
       FIG. 4  shows a three-dimensional schematic view of an alignment of a distance adjusting module  140  of the linear actuator  10  of the embodiment of  FIG. 1 . Please refer to  FIG. 4  with reference to  FIG. 3 , the semi-finished product  100  can further include a distance adjusting module  140  configured to defect the elevating distance of the threaded shaft  200 . The distance adjusting module  140  is detachably disposed at the case  110  and includes a module housing  141  and a circuit board  142 . The circuit board  142  is received within the module housing  141 . When the distance adjusting module  140  is assembled with the case  110 , the circuit board  142  is electrically connected to the driving module  120 . The circuit board  142  can include micro switches (not shown), and the distance adjusting module  140  can further include a slave wheel (not labeled) to be engaged with the gear of the driving module  120 . 
     As shown in  FIGS. 3 and 4 , the driving module  120  can further include a connecting portion  122  electrically connected to the motor  121 , and the connecting portion  122  exposes from the case  110 . The distance adjusting module  140  can further include an inserting portion  143  electrically connected to the circuit board  142  and corresponding to the connecting portion  122 . The inserting portion  143  can include a plurality of pins, and the connecting portion  122  can include a plurality of pin holes corresponding to a plurality of wires of the motor  121 , respectively. As the inserting portion  143  is inserted into the connecting portion  122 , the circuit board  142  can be electrically connected to the motor  121  via the inserting portion  143  and the connecting portion  122 , and can detect the elevating distance of the threaded shaft  200  in real-time. The distance adjusting module  140  can further include another inserting portion (not shown) configured to connect to an outer controller (not shown). The outer controller can receive the elevating distance of the threaded shaft  200  detected by the distance adjusting module  140  to stop the motor  121  according to a predetermined distance setting. 
     Precisely, the case  110  can further include an engaging groove  1101 , the module housing  141  can further include an engaging tab  1141 , and the shape of the engaging groove  1101  fits the shape of the engaging tab  1141 . When the engaging tab  1141  is engaged with the engaging groove  1101 , the distance adjusting module  140  is secured at the case  110 , and the inserting portion  143  is inserted into the connecting portion  122  of the driving module  120  to complete the electric connection between the driving module  120  and the distance adjusting module  140 . Finally, the module housing  141  can be secured at the case  110  by screws. If the user would like to remove the distance adjusting module  140 , the screws can be unscrewed and the distance adjusting module  140  can be pulled out along the engaging groove  1101  to allow the inserting portion  143  to disengage from the connecting portion  122 , thereby removing the distance adjusting module  140 . 
       FIG. 5  shows a partial three-dimensional schematic view of the linear actuator  10  of the embodiment of  FIG. 1 . As shown in  FIGS. 3 to 5 , the semi-finished product  100  can further include a reinforcing seat  150  and an end cap  160 . The reinforcing seat  150  is disposed within the case  110  and connected to the main gear  131 . The reinforcing seat  150  includes a reinforcing seat body  151  and at least one installed hole  152  disposed on the reinforcing seat body  151 . The reinforcing seat  150  can share the loads on the case  110  during an operation of the linear actuator  10 . The end cap  160  is detachably connected to the reinforcing seat  150  and includes an end cap body  161  and at least one through hole  162  corresponding to the at least one installed hole  152  and configured for at least one fastening screw to screw therewith. The at least one fastening screw passes the at least one through hole  162  to screw with the at least one installed hole  152  so as to allow the end cap  160  to be secured at the reinforcing seat  150 . In other embodiments, the case and the reinforcing seat can be combined in other methods, and the present disclosure is not limited thereto. 
       FIG. 6  shows a block diagram of a linear actuator assembling method S 1  according to another embodiment of the present disclosure. Please refer to  FIG. 6  with references to  FIGS. 1 to 5 , the linear actuator assembling method S 1  includes a semi-finished product assembling step S 2  and a threaded shaft assembling step S 3 . The semi-finished product assembling step S 2  is to form a semi-finished product  100 , and the semi-finished product  100  includes a case  110 , a main gear  131 , and a main gear bearing  132 . The main gear  131  and the main gear bearing  132  are surrounded and restricted by the case  110 , and the main gear bearing  132  is sleeved on the main gear  131 . In the threaded shaft assembling step S 3 , a threaded shaft  200  is reversely assembled, and one end of the threaded shaft  200  is inserted into the main gear  131  to allow the end of the threaded shaft  200  to be restricted by the main gear  131 . 
     To be more specific, in the semi-finished product assembling step S 2 , a distance adjusting module  140  is allowed to be engaged with the case  110  and to be electrically connected to a driving module  120  of the semi-finished product  100 , and therefore the distance adjusting module  140  is favorable for the user to quickly remove from or install into the case  110  for checking or changing purpose. In the threaded shaft assembling step S 3 , the end of the threaded shaft  200  is allowed to expose from the main gear  131 , a spacer  170  is sleeved on the end of the threaded shaft  200 , and then a punch riveting process is used to restrict the threaded shaft  200 . In other embodiments, the threaded shaft can be restricted by the main gear via pins or key grooves to quickly assembled, and the present disclosure is not limited thereto. The other end of the threaded shaft  200  is configured to combine an elevating mechanism  300 . The elevating mechanism  300  linked with the threaded shaft  200  can move linearly relative to the linear actuator  10 . In other embodiments, the elevating mechanism can be modified to apply in other fields based on the demands, and the present disclosure is not limited thereto. 
     The semi-finished product  100  can further include a reinforcing seat  150  disposed within the case  110  and sleeved on the main gear bearing  132 . The reinforcing seat  150  can further include at least one installed hole  152  corresponding to at least one opening  133  of the main gear  131 . In the semi-finished product assembling step S 2 , a fixture (not shown) can be used to pass the at least one installed hole  152  and the at least one opening  133  to restrict a rotation of the main gear  131 , and then the threaded shaft  200  is fastened therewith. Therefore, the installed hole  152  can be configured for the fixture to pass therethrough for restricting the main gear  131 , and, in the later process, the installed hole  152  can be configured for an end cap  160  to fasten therewith. Moreover, the opening  133  on the main gear  131  is favorable for losing weight and decreasing cost, and the structure can have lots of functions. 
     Additionally, the linear actuator assembling method S 1  can further include an end cap assembling step S 4 , and the end cap  160  is allowed to connect to the semi-finished product  100 . Hence, the protection effect and the anti-dust effect can be achieved. 
     As described above, the present disclosure is to assemble the components other than the threaded shaft  200  into a semi-finished product  100 , the threaded shaft  200  that is suitable for the demands can then be chosen and assembled by the user, and the assembling efficiency and convenience of the linear actuator  10  can be increased. 
     Although the present disclosure has been described in considerable detail with reference to certain embodiments thereof, other embodiments are possible. Therefore, the spirit and scope of the appended claims should not be limited to the description of the embodiments contained herein. 
     It will be apparent to those skilled in the art that various modifications and variations can be made to the structure of the present disclosure without departing from the scope or spirit of the disclosure. In view of the foregoing, it is intended that the present disclosure covers modifications and variations of this disclosure provided they fall within the scope of the following claims.