Patent Publication Number: US-8539683-B2

Title: Stamping machine

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     Pursuant to 35 U.S.C. §119(a), this application claims the benefit of earlier filing date and right of priority to Japanese Patent Application No. 2010-005310, filed on Jan. 13, 2010, the contents of which is hereby incorporated by reference herein in its entirety. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to an engraving device that forms an image on a surface of an object. 
     2. Discussion of the Related Art 
     In general, an engraving device forms an image on the surface of an object by engraving a plurality of marks on a surface of an object composed of a relatively formable material such as gold, platinum, brass, aluminum, or stainless steel. For example, an engraving device may form a desired image on an object by driving a tip of an engraving rod into a surface of an object to form a plurality of dot engraved marks in the surface of the object. 
     In prior art engraving devices, dust or other foreign matters generated during the engraving process would tend to enter a displacement mechanism, thereby making the maintenance of the displacement mechanism cumbersome. 
     The present invention has been made to overcome the above problem, and it is an object of the present invention to provide an engraving device that can reduce the burden of maintenance by preventing entrance of foreign matters into a displacement mechanism that displaces a working tool for engraving an object. 
     SUMMARY OF THE INVENTION 
     Features and advantages of the invention will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings. 
     In accordance with an embodiment, an engraving device that forms a desired image via a plurality of engraved marks in a surface of an object via a working tool is presented. The engraving device includes a base comprising a retainer configured to retain the object, a X-direction displacement means located above the base, configured to displace the working tool along a X-axis along the surface of the object, a Y-direction displacement means located above the base, configured to displace the working tool along a Y-axis perpendicular to the X-axis along the surface of the object, and a Z-direction displacement means located above the base, configured to displace the working tool along a Z-axis toward and away from the object. 
     According to one feature wherein the Z-direction displacement means comprises a Z-direction feed screw that is provided along the Z-axis on the base, and a lifting element that is engaged with the Z-direction feed screw and movable along the Z-axis, and the X-direction displacement means and the Y-direction displacement means are provided on the lifting element. 
     According to another feature a space that is opened in at least one of the X-direction and the Y-direction is formed around the base. 
     According to yet another feature, the engraving device includes a control means configured to control the operations of the X-direction displacement means, the Y-direction displacement means and the Z-direction displacement means, wherein the control means is located above the base. 
     In accordance with another embodiment, an engraving device is presented. The engraving device includes a body, a first guide rod that is supported by the body and extends vertically, a lifting element that is movable vertically along the first guide rod, the lifting element comprising a second guide rod that extends in a longitudinal direction, a third guide rod that extends in a lateral direction, and a carriage that retains a working tool for engraving marks on a surface of an object, wherein a slide base is supported by the second guide rod or the third guide rod for movement on the guide rod in an axial direction thereof, and wherein the carriage is supported on the third guide rod for movement in an axial direction of the third guide rod. 
     These and other embodiments will also become readily apparent to those skilled in the art from the following detailed description of the embodiments having reference to the attached figures, the invention not being limited to any particular embodiment disclosed. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above and other aspects, features, and advantages of the present invention will become more apparent upon consideration of the following description of preferred embodiments, taken in conjunction with the accompanying drawing figures. 
         FIG. 1  is an external perspective view of an engraving device according to one embodiment of the present invention. 
         FIG. 2  is a partially cutaway perspective view of the engraving device illustrated in  FIG. 1 . 
         FIG. 3  is a block diagram of a control system that controls the operation of the engraving device according to one embodiment of the present invention. 
         FIG. 4  is a schematic view illustrating the relationship of an X-direction displacement means and a Y-direction displacement means to a Z-direction displacement means in the engraving device according to one embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     In the following detailed description, reference is made to the accompanying drawing figures which form a part hereof, and which show by way of illustration specific embodiments of the invention. It is to be understood by those of ordinary skill in this technological field that other embodiments may be utilized, and structural, electrical, as well as procedural changes may be made without departing from the scope of the present invention. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or similar parts. 
     It should be noted that the drawings used herein are schematically depicted to facilitate understanding of the present invention, for example, some elements may be exaggerated. Thus, the dimensions and proportions between constituent elements may be different. In addition, the lateral direction of the drawing, the depth direction of the drawing, and the vertical direction of the drawing are defined as X-direction, Y-direction, and Z-direction, respectively, as indicated by the coordinate axes that are shown in  FIGS. 1 ,  3 , and  4 . The engraving device  100  is a processing device that forms a plurality of dot engraved marks in a surface of a workpiece WK to form a desired image in the surface of the workpiece WK. 
     As illustrated in  FIG. 1 , the engraving device  100  is provided with a base  101 . The base  101 , which carries and securely retains a workpiece WK as a target of engraving, may be formed by bending a plate into a rectangular box shape. The base  101  is provided with a power supply switch  101   a  for the engraving device  100  on its front face, and a workpiece positioning area  101   b  to receive a workpiece. At a central portion of the workpiece positioning area, four mounting holes  101   c  are provided for use in attaching a retainer WC for retaining the workpiece WK. Support pillars  102   a  and  102   b  are provided in an upright position at both ends of a surface of the base  101  behind the workpiece positioning area  101   b.    
     The support pillars  102   a  and  102   b  may support a carriage  120  and are formed to extend in the Z-direction as illustrated in  FIG. 1 . A controller box  103  may be provided on the back side of the engraving device  100  ( FIG. 2 ) and supported by the pillars  102   a  and  102   b . At the upper ends of the support pillars  102   a  and  102   b , a top frame  104  is provided across the support pillar  102   a  and support pillar  102   b . As shown in  FIG. 4 , the top frame  104  is a box which may be formed of a plate and which supports upper ends of a Z-direction feed motor  105  and a Z-direction feed screw  106 , and accommodates a driving gear  105   a  and a driven gear  106   a  that transmit the driving force of the Z-direction feed motor  105  to the Z-direction feed screw  106 . 
     The Z-direction feed motor  105  is an electric motor, the operation of which is controlled by the controller  130 , and rotatably drives the Z-direction feed screw  106 . The Z-direction feed motor  105  is securely attached to a lower surface of the top frame  104  with its drive shaft extending into the top frame  104  through the bottom thereof. At the end of the drive shaft in the top frame  104 , a driving gear  105   a , which rotates together with the drive shaft, is attached. 
     The Z-direction feed screw  106  is a rod body, a spiral male thread with a trapezoidal cross-section is formed around the Z-direction feed screw  106 , and is provided in an upright position in the Z-direction. One end of the Z-direction feed screw  106  extends into the top frame  104  through the bottom thereof, and the driven gear  106   a , which meshes with the driving gear  105   a  of the Z-direction feed motor  105 , is provided at the end. That is, the Z-direction feed screw  106  is coupled to the Z-direction feed motor  105  via the driving gear  105   a  and the driven gear  106   a . The other end of the Z-direction feed screw  106  is rotatably supported by a pivotal support frame  107  provided on the base  101 . The pivotal support frame  107  is a table that may be formed of a steel plate and provided in a protruded fashion on the base  101 , which faces the top frame  104  from below. 
     The Z-direction feed screw  106  is threaded with a feed nut  108   a  that is provided in a lifting base  108 . The lifting base  108  is a plate-shaped body with sidewalls that are formed by bending the four sides of a flat plate downward, and is supported by the Z-direction feed screw  106  via the feed nut  108   a , which extends through the lifting base  108  in the Z-direction. On each of the sidewalls of the lifting base  108 , guide sleeves are provided, respectively.  FIG. 2  illustrates a guide sleeve  108   b  attached to one sidewall of the lifting base  108 . 
     The guide sleeves are cylindrical bodies through which guide shafts  109   a  and  109   b  slidably extend, respectively ( FIG. 2 ), the guide sleeves are provided between the base  101  and the top frame  104  in an upright position. The lifting base  108  may be displaced up and down in the Z-direction along the guide shafts  109   a  and  109   b  by rotation of the Z-direction feed screw  106  via the Z-direction feed motor  105 . A screw feed mechanism that is constituted on the Z-direction feed motor  105 , the Z-direction feed screw  106 , and the feed nut  108   a  correspond to a Z-direction displacement means. 
     In addition, a Y-direction feed motor  110  is provided on the sidewall of the lifting base  108 . The Y-direction feed motor  110  is an electric motor, the operation of which is controlled by the controller  130 , and rotatably drives a Y-direction feed screw  113 . A slide base body  112  is supported inside of the sidewalls of the lifting base  108  via two guide shafts  111   a  and  111   b  ( FIGS. 1 and 2 ). The guide shafts  111   a  and  111   b  are disposed parallel to each other in the Y-direction in the lifting base  108 , and support the slide base body  112  for sliding movement in the Y-direction. 
     The slide base body  112  is a plate that supports the carriage  120 , and has a plurality of sidewalls formed by bending a plate or joining plates. At an upper end of the slide base body  112 , sidewalls are provided parallel to each other in the X-direction and in an upright position in the Z-direction. The guide shafts  111   a  and  111   b  slidably extend through the sidewalls. The Y-direction feed screw  113  extends via a feed nut  112   a  through a sidewall. 
     The Y-direction feed screw  113  is a spiral male thread rod with a trapezoidal cross-section and is provided horizontally in the Y-direction. One end of the Y-direction feed screw  113  is coupled to the Y-direction feed motor  110 , and the male thread portion of the Y-direction feed screw  113  is threaded with the feed nut  112   a , which is provided on the slide base body  112 . Thus, the slide base body  112  is displaced in the Y-direction in the drawing along the guide shafts  111   a  and  111   b  by rotational driving of the Y-direction feed screw  113 . A screw feed mechanism that is constituted on the Y-direction feed motor  110 , the Y-direction feed screw  113 , and the feed nut  112   a  correspond to a Y-direction displacement means. 
     Two guide shafts  114   a  and  114   b  and an X-direction feed screw  115  are provided between sidewalls extending parallel to each other in the Y-direction. The guide shafts  114   a  and  114   b  are provided parallel to each other and support the carriage  120  for sliding movement in the X-direction. The X-direction feed screw  115  is a spiral male thread rod with a trapezoidal cross-section and is provided horizontally in the X-direction. One end of the X-direction feed screw  115  is coupled to an X-direction feed motor  116 , and the male threads portion of the X-direction feed screw  115  is threaded with a feed nut (not shown) provided in the carriage  120 . 
     The X-direction feed motor  116  is an electric motor that rotatably drives the X-direction feed screw  115 , and is securely provided on a sidewall of the slide base body  112 . The operation of the X-direction feed motor  116  is controlled by the controller  130 . The carriage  120  is displaced along the guide shafts  114   a  and  114   b  in the X-direction by rotational driving of the X-direction feed screw  115 . A screw feed mechanism that is constituted on the X-direction feed motor  116 , the X-direction feed screw  115 , and a feed nut (not shown) provided in the carriage  120  correspond to an X-direction displacement means. 
     The elements that constitute the Y-direction displacement means and X-direction displacement means are attached to the lifting base  108  directly or via the slide base body  112 . Thus, the Y-direction displacement means and X-direction displacement means are displaced up and down in the Z-direction with the lifting base  108  when the lifting base  108  is lifted up and down by the Z-direction displacement means. 
     The carriage  120  is a mechanical device which removably retains a generally needle-shaped working tool  121  that forms dot engraved marks on a surface of the workpiece WK and which vibrates the working tool  121  in a specific direction. Specifically, the carriage  120  has a generally cylindrical holder  122 , a solenoid  123  ( FIG. 3 ), and a spring (not shown) which are provided in the holder  122 . The solenoid  123  is a cylindrical electromagnetic functional component that converts electrical energy into linear motion and thrusts the working tool  121  in a downward motion when energized. The driving of the solenoid  123  is controlled by the controller  130 . 
     The spring is disposed below the solenoid  123 , and pushes back the working tool  121  which is extended from the lower end of the solenoid  123 . That is, the carriage  120  thrusts the working tool  121  downward by energizing the solenoid  123  and retracts the working tool  121  upward by de-energizing the solenoid  123  and using the biasing force of the spring. The working tool  121  is formed of a material which is harder than the workpiece WK, such as a cemented carbide alloy, a diamond, or an artificial diamond. 
     The controller  130  includes a microcomputer that includes components such as a CPU, a ROM, and a RAM, and controls the operations of the Z-direction feed motor  105 , the Y-direction feed motor  110 , the X-direction feed motor  116 , and the solenoid  123  according to a command from an external computer device  140  that is connected to the controller  130  via an interface  131 . The controller  130  is located in the controller box  103 , which is provided on the back side of the engraving device  100  on the base  101 . 
     The external computer device  140  ( FIG. 3 ) includes a microcomputer that includes components such as a CPU, a ROM, a RAM, and a hard disk, and controls the operation of the engraving device  100  by executing a processing program (not shown) according to a command from an input device  141 , such as a keyboard or a mouse. In this example, the processing program is stored in the hard disk. The external computer device  140  displays the operating conditions of the engraving device  100  and the execution status of the processing program on a display device  142 . A personal computer (PC) is an example of the external computer device  140 . It should be noted that the external computer device  140  may be any form of computer device which can control the operation of the engraving device  100 . 
     The operation of the engraving device  100  will now be described. First, the operator connects the external computer device  140  and the engraving device  100  via the interface  131 , and turns on the power supplies for the external computer device  140  and the engraving device  100 . In this example, the operator activates various circuits of the engraving device  100  including the controller  130  by operating the power supply switch  101   a  provided on the front face of the base  101  of the engraving device  100 . As a result, the external computer device  140  executes a prescribed program (not shown) and turns to a standby state to wait for a command from the operator. 
     The engraving device  100  may execute a prescribed program (not shown) that is stored in the ROM to return the carriage  120  to the origin position and then turns to a standby state to wait for a command from the external computer device  140 . Next, the operator sets a workpiece WK in the workpiece positioning area  101   b  on the base  101  of the engraving device  100 . In this example, the operator may use a retainer WC for use in securing the workpiece WK in the workpiece positioning area  101   b  on the base  101 . The workpiece WK can be set on the base  101  without regard to the length thereof. That is, a workpiece WK with a various shape can be set on the base  101  by placing the workpiece WK with its longitudinal direction matching the X-direction on the base  101 . 
     Next, the operator operates the input device  141  of the external computer device  140  to command the external computer device  140  to execute a processing program (not shown). The processing program is a program that creates processing data corresponding to a desired image and outputs the data to the engraving device  100  in order to form a desired image in a surface of the workpiece WK. In response to this command, the external computer device  140  executes the processing program. 
     Specifically, the external computer device  140  prompts the operator to input image data. In response, the operator inputs a desired image into the external computer device  140  via an image capture device such as a scanner. As a result, image data representing the desired image is stored in the memory of the external computer device  140 . In this example, the image data may be in a raster data format. Alternatively, the operator may create an image on the external computer device  140  via an image drawing software. The image data may be in a vector format such as outlines of letters. 
     Next, the external computer device  140  creates engraving process data based on the image data. The engraving process data is data which operates the engraving device  100  in order to form dot engraved marks on a surface of the workpiece WK. In this example, the external computer device  140  creates the engraving process data based on the degree of luminosity of black and white included in the image data. That is, the engraving process data is created to form engraved marks with different depths that correspond to different degrees of luminosity of black and white that are included in the image data. The depths of the engraved marks represent the degrees of shading of the image that is formed on the workpiece WK. 
     The external computer device  140  then outputs the engraving process data to the engraving device  100 . The engraving device  100  temporarily stores the engraving process data that has been output from the external computer device  140  in the RAM of the controller  130 , and controls the operations of the Z-direction feed motor  105 , the Y-direction feed motor  110 , the X-direction feed motor  116 , and the solenoid  123  based on the temporarily stored engraving process data. 
     Specifically, the controller  130  controls the operation of the solenoid  123  to drive the tip of the working tool  121  into the surface of the workpiece WK intermittently while controlling the operations of the Z-direction feed motor  105 , the Y-direction feed motor  110 , and the X-direction feed motor  116  to change the position of the end of the working tool  121  relative to the workpiece WK. In this example, the carriage  120  is displaced in the Z-direction together with the lifting base  108  in accordance with the vertical displacement thereof and is displaced in the Y-direction and X-direction by driving the Y-direction feed motor  110  and the X-direction feed motor  116 . As a result, an image is formed on the surface of the workpiece WK, the image comprising a multiplicity of engraved marks. 
     In this example, X-direction displacement refers to the X-direction feed motor  116 , the X-direction feed screw  115 , and the feed nut provided in the carriage  120 . Y-direction displacement means refers to the Y-direction feed motor  110 , the Y-direction feed screw  113 , and the feed nut  112   a . Z-direction displacement means refers to the Z-direction feed motor  105 , the driving gear  105   a , the Z-direction feed screw  106 , the driven gear  106   a , and the feed nut  108   a . Accordingly, the X-direction displacement means, the Y-direction displacement means, and the Z-direction displacement means prevent the dust that is generated during processing of the workpiece WK from entering the respective components. 
     The image on the workpiece WK is formed by the working tool  121 , which is displaced relative to the workpiece WK in a stationary state. Thus, the engraving device  100  does not require a mechanical structure that is used to displace a large workpiece WK and can reduce errors in processing accuracy which are caused by displacing a large workpiece WK. When the processing based on the engraving process data is fully completed, the controller  130  returns the carriage  120  to the position of origin. 
     Accordingly, when the external computer device  140  stops executing the processing program and returns to a standby state, the engraving device  100  also returns to a standby state. The operator may then remove the workpiece WK from the base  101  and finish the processing work. When the image is formed on another workpiece WK, the operator sets the other workpiece WK on the base  101  and executes the processing program. 
     As can be understood from the above description of operation, according to the above embodiment, the X-direction displacement means, Y-direction displacement means, and Z-direction displacement means displace the working tool  121  relative to the workpiece WK in three axial directions along the X, Y, and Z, axis, respectively. Thus, the dust that is generated during processing of a workpiece WK is unlikely to enter the components that constitute the X-direction displacement means, Y-direction displacement means, and Z-direction displacement means. As a result, the burden of maintenance of the X-direction displacement means, Y-direction displacement means, and Z-direction displacement means, is reduced. In addition, preventing the entrance of foreign matter into the X-direction displacement means, Y-direction displacement means, and Z-direction displacement means also reduces errors in processing accuracy. 
     It should be noted that the present invention is not limited to the above embodiments and various modification may be mode without departing from the object of the present invention. 
     For example, in the embodiment described above, each of the X-direction displacement means, Y-direction displacement means, and Z-direction displacement means includes a screw feed mechanism. However, the X-direction displacement means, Y-direction displacement means, and Z-direction displacement means are not necessarily limited to the above embodiment as long as the carriage  120  can be displaced along the X, Y, and Z axis. For example, a displacing object, such as the carriage  120  or the slide base body  112 , may be displaced by coupling a belt or wire that is wound around a pulley to the displacing object and driving the pulley with a feed motor. 
     In the above embodiment, the engraving device  100  is configured to form an open space, in the X-direction, above the workpiece positioning area  101   b  on the base  101 . However, the engraving device  100  may be configured to form an open space, in the Y-direction, above the workpiece positioning area  101   b  on the base  101 . When there is no need to process a large workpiece WK, the engraving device  100  does not need to be configured to form the open spaces in the X-direction and Y-direction above the workpiece positioning area  101   b.    
     In the above embodiment, the controller  130  is disposed in the controller box  103 , which is provided on the back side of the engraving device  100  above the base  101 . This prevents the dust that is generated during processing of a workpiece WK from attaching to the controller  130 . However, the controller  130  may also be protected from dust by, for example, placing it a box. In other words, the controller  130  may be located in the base  101 , for example. 
     While the engraving process data is created by the external computer device  140  in the above embodiment, the present invention is not limited to creating process data in the external computer device  140 . For example, the engraving device  100  may be provided with an input device or a display device and the processing program may be stored in the RAM or ROM of the controller  130  so that the engraving process data can be created based on a desired image. That is, the engraving device  100  may be provided with a function of creating engraving process data. In this example, the external computer device  104  is unnecessary. 
     In the above embodiment, the lifting base  108  that is displaced in the Z-direction by driving of the Z-direction feed motor  105  is provided with the Y-direction displacement means and X-direction displacement means separately. Specifically, the lifting base  108  corresponds to a lifting element. The shape and size of the lifting base  108  is not limited to the above embodiment, and may be determined appropriately depending on the Y-direction displacement means, X-direction displacement means, and the carriage  120  which are attached thereto. In addition, the engraving device  100  may be constructed without the lifting base  108 . For example, Z-direction displacement means and X-direction displacement means may be attached to a Y-direction displacing element, which corresponds to the lifting base  108  that is displaced in the Y-direction by the Y-direction feed motor  110 . 
     The foregoing embodiments and advantages are merely exemplary and are not to be construed as limiting the present invention. The present teaching can be readily applied to other types of apparatuses and processes. The description of the present invention is intended to be illustrative, and not to limit the scope of the claims. Many alternatives, modifications, and variations will be apparent to those skilled in the art.