JP5128206B2 - Linear guide device - Google Patents

Description

  The present invention is a linear guide in which a moving block is assembled to a track rail via a number of balls that circulate indefinitely, and a mounted object fixed to the moving block can freely reciprocate along the track rail. More particularly, the present invention relates to a linear guide device having a simple structure in which an infinite circulation path of a ball is formed as a track groove facing a track rail with respect to the moving block.

  In a work table of a machine tool and a linear guide portion of various conveying devices, a linear guide device in which a moving block on which a movable body such as a table is continuously moved along a track rail is frequently used. In this type of linear guide device, the moving block is assembled to the track rail via a large number of balls, and the ball moves by applying a load between the moving block and the track rail. The movable body mounted on the block can be moved lightly with very little resistance along the track rail. Further, the moving block is provided with an infinite circulation path of the ball, and the moving block can continuously move along the track rail by circulating the ball in the infinite circulation path. Yes.

  Conventionally, the moving block has been mainly composed of a metal block main body and a synthetic resin end cap coupled to both ends of the block main body. A load rolling groove is formed in the block body so that the ball rolls while applying a load between the ball rolling groove of the track rail, and an unloaded ball path is provided in parallel with the loaded rolling groove. In order to suppress wear over time with respect to the rolling of the ball, it was formed of, for example, steel that can be hardened. In addition, a direction changing path is formed in the end cap, and the end cap is formed by injection molding of a synthetic resin in order to realize a complicated shape. Then, by accurately fixing the pair of end caps to the front and rear end faces of the block body, the end of the load rolling path and the end of the unloaded ball path are connected by a direction change path, and the ball endless A moving block with a circulation path was completed.

  However, such a conventional moving block has a problem that it takes time and effort to process and assemble, and the manufacturing cost increases. In particular, in a linear guide device for heavy load applications, in order to increase the number of effective balls that are loaded, the block body is elongated along the moving direction, so that no load balls are applied to the block body. It was difficult to drill the passage.

  On the other hand, WO2006 / 022242-A1 discloses a linear guide device in which the configuration of a moving block is extremely simplified. In this linear guide device, the infinite circulation path of the ball is formed as a track groove with respect to the metal moving block, and the moving block is composed of a single metal piece. The track grooves are provided on both ends of the load linear grooves, and the load linear grooves on which the balls roll while being loaded with the ball rolling grooves of the track rail. A pair of ball deflection grooves for changing the rolling direction of the balls that have been moved to release the balls from the ball rolling grooves of the track rail, and a ball in an unloaded state from one ball deflection groove to the other ball deflection groove And a no-load straight groove for transporting. The track groove is formed at a position facing the track rail of the moving block, so that a ball that rolls in an unloaded state inside the ball deflection groove and the no-load linear groove does not leave the track groove. ing.

A similar linear guide device is also disclosed in WO 2006 / 064734-A1. In this linear guide device, the track groove is formed in a ball circulation plate separate from the moving block, and the ball groove plate is fitted to the moving block so that the track groove is provided at a position facing the track rail. It is possible.
WO2006 / 022242-A1 WO2006 / 064374-A1

  However, in the conventional linear guide device in which the track groove is formed with respect to the moving block made of a single metal piece, the track groove is provided in the moving block by cutting or grinding. There may be errors in the position of the unloaded straight grooves and the parallelism of these grooves. If such errors occur, smooth circulation of the balls is hindered, and the moving block moves relative to the track rail. There was a problem that resistance increased.

  Moreover, if all of the loaded straight grooves, unloaded straight grooves and the ball deflection grooves connecting them are formed by cutting or grinding, the productivity is extremely poor and the linear guide device is provided to the customer at low cost. There was also a problem that it was difficult to do.

  The present invention has been made in view of such problems, and the object of the present invention is to be able to accurately and inexpensively form a track groove serving as an infinite circulation path for a ball with respect to a moving block. Another object of the present invention is to provide a linear guide device that can ensure a smooth circulation of a ball, and consequently a smooth movement of a moving block with respect to a track rail, and can be supplied to a consumer at a lower cost.

  That is, the linear guide device according to the present invention is formed of a track rail having a substantially rectangular cross section and having one ball rolling groove on each side surface along the longitudinal direction, a horizontal web, and the horizontal web. It has a pair of projecting flange portions, is formed in a channel shape having a guide groove, and is composed of a moving block that is assembled via a plurality of balls to a track rail that is loosely fitted in the guide groove. The moving block is provided with a track groove serving as an infinite circulation path for the ball. The track groove includes a load straight groove disposed on an inner surface of the flange portion of the moving block so as to face the ball rolling groove of the track rail, and the load straight line with respect to a lateral web or the flange portion of the moving block. The unloaded straight groove is disposed in parallel with the groove and opened toward the track rail, and the ball deflecting groove connects the loaded straight groove and the unloaded straight groove. The moving block is fixed to the metal block main body in which the load linear groove and the unloaded linear groove are formed by plastic working, and both front and rear end surfaces in the moving direction of the block main body, and the ball deflection groove It comprises a pair of end plates provided.

  According to such a linear guide device of the present invention, the moving block is divided into a metal block main body and a pair of end plates fixed to both end faces of the block main body, and a track groove is formed in the block main body. Since only the loaded straight groove and the unloaded straight groove are formed, the block main body can be manufactured by die forging or plastic working such as drawing using a die. Therefore, the shape of the die used for forging and the die used for drawing is transferred to the block body to form the load linear groove and the no-load linear groove, so that these grooves can be formed with high accuracy. Smooth infinite circulation of the ball in the track groove can be achieved.

  In addition, if the loaded straight groove and the unloaded straight groove are formed using plastic working such as die forging or drawing, the machining time can be shortened compared to the case of using cutting or grinding, Accordingly, the productivity of the moving block is improved, and the linear guide device can be supplied to the consumer at a low cost.

  In the present invention, when considering the dimensional accuracy of the block body, the die forging or drawing is preferably a cold treatment. Moreover, after forming a block main body by die forging, drawing, etc., when the dimensional accuracy of this block main body is not preferable, the dimension correction of a block main body may be performed by sizing.

  Further, as the die forging process, as long as the block main body is finished to a desired dimensional accuracy and the load linear groove and the no-load linear groove can be formed with high accuracy, an open type, a semi-sealed type Alternatively, it may be carried out using any type of sealed mold. However, from the viewpoint of processing the load linear groove and the no-load linear groove with higher accuracy with respect to the block main body, it is preferable to manufacture the block main body by hermetic cold die forging.

  Hereinafter, the linear guide device of the present invention will be described in detail with reference to the accompanying drawings.

  1 and 2 show an example of a linear guide device to which the present invention is applied. This linear guide device includes a long track rail 1 having a substantially rectangular cross section, and a moving block 2 formed in a channel shape and assembled to the track rail 1 via a large number of balls 3. The moving block 2 is configured to freely reciprocate on the track rail 1 so as to straddle the track rail 1.

  One rolling groove 10 for each ball 3 is formed on each side surface of the track rail 1 along the longitudinal direction. In addition, slightly above the rolling grooves 10, the upper corners of the track rail 1 are cut obliquely, and a no-load ball auxiliary surface 11 described later is formed. Therefore, the track rail 1 has a substantially trapezoidal shape above the portion where the ball rolling groove 10 is formed. As shown in FIG. 3, the rolling groove 10 is composed of two concave curved surfaces 10a and 10b on which the ball 3 rolls, and its cross section has a so-called Gothic arch shape. Therefore, the ball 3 comes into contact with the concave curved surfaces 10a and 10b at two points, and the contact directions have an angle of 45 degrees with respect to the bottom surface of the track rail 1, respectively. In addition, a plurality of bolt mounting holes 12 are formed through the track rail 1 at predetermined intervals in the longitudinal direction, and the track rail 1 is used as a bed, a column, or the like of various mechanical devices by using the bolt mounting holes 12. It can be attached to the fixed part.

  On the other hand, the moving block 2 has a lateral web 20 and a pair of flange portions 21, 21 orthogonal to the lateral web 20 and is formed in a channel shape, and a guide groove 22 is formed between the pair of flange portions 21. Have. As shown in FIG. 1, the moving block 2 has the upper portion of the track rail 1 loosely fitted in the guide groove 22 and straddles the track rail 1 through a slight gap. That is, both side surfaces of the track rail 1 are opposed to the inner surface of the flange portion 21 of the moving block 2. The upper surface of the horizontal web 20 is a mounting surface 23 for a movable body such as a table, and the horizontal web 20 has a tap hole 24 into which a mounting screw is screwed.

  The moving block 2 has a track groove 30 in which the balls 3 circulate infinitely. The track groove 30 is opposed to the rolling groove 10 of the track rail 1 and is formed in parallel with the load straight groove 31 formed on the inner surface of the flange portion 21, and the track rail 1. The unloaded linear groove 32 formed opposite to the unloaded ball auxiliary surface 11 and a ball deflection groove 33 for moving the ball 3 between the loaded linear groove 31 and the unloaded linear groove 32. Yes. The track groove 30 is open toward the track rail 1 in the entire area, and the balls 3 arranged in the track groove 30 circulate in the track groove 30 while facing the track rail 1.

  FIG. 4 shows a state in which the track groove 30 is developed on a plane. The load straight groove 31 constituting a part of the track groove 30 has a cross section formed in a Gothic arch shape like the rolling groove 10 on the track rail 1 side. Touching at two points. Accordingly, the contact direction between the ball 3 and the load straight groove 31 is inclined 45 degrees upward and downward with respect to the normal direction of the inner surface of the flange portion 21 (the left-right direction in the drawing of FIG. 3). The ball 3 rolls while applying a load between the rolling groove 10 of the track rail 1 and the load linear groove 31 of the moving block 2, and the moving block 2 applies all loads acting in directions other than the moving direction. It can reciprocate along the track rail 1.

  On the other hand, the no-load linear groove 32 constituting a part of the track groove 30 is formed as a passage having an inner diameter slightly larger than the diameter of the ball 3, and the ball 3 is in a no-load state, that is, a state where it can freely rotate. It is accommodated in the no-load rolling groove 32 as it is. Further, the opening width of the unloaded straight groove 32 is set to be larger than the diameter of the ball 3, and the ball 3 is held inside the unloaded straight groove 32 in contact with the track rail 1.

  The ball deflection groove 33 has a substantially U-shaped track connecting the load straight groove 31 and the no-load straight groove 32, and the ball 3 that has rolled on the load straight groove 31 while applying a load. Is released from the load, and the rolling direction of the ball 3 is gradually changed to change its direction by 180 degrees and fed into the unloaded straight groove 32. The ball deflection groove 33 is formed so as to be shallowest at the connection portion with the load straight groove 31 and deepest at the connection portion with the no-load straight groove 32. When the ball 3 rolling on the load straight groove 31 enters the ball deflection groove 33 due to the deepening of the ball deflection groove 33, the ball 3 is released from the load and becomes in an unloaded state. It advances toward the no-load linear groove 32 in 33, and enters the no-load linear groove 32 as it is.

  When the moving block 2 is moved along the track rail 1, the ball 3 sandwiched between the ball rolling groove 10 of the track rail 1 and the load straight groove 31 of the moving block 2 is moved to the track rail 1. 2 moves within the load linear groove 31 at a speed 0.5 V which is half of the moving speed V of 2. When the ball 3 rolling in the load linear groove 31 reaches the ball deflection groove 33, the depth of the ball deflection groove 33 gradually increases as described above, and is gradually released from the load. The ball 3 released from the load travels in the rolling groove 10 of the track rail 1 as it is pushed by the subsequent ball 3, but the ball deflection groove 33 blocks the rolling of the ball 10 in the rolling groove 10. Since the traveling direction of the ball 3 is forcibly changed, the ball 3 is brought close to the concave curved surface 10a of the rolling groove 10 by the ball deflection groove 33, and crawls up the concave curved surface 10a to the side surface of the track rail 1. Lift up. As a result, the ball 3 is completely separated from the rolling groove 10 of the track rail 1 and is completely accommodated in the ball deflection groove 33 of the moving block 2.

  As shown in FIG. 4, since the ball deflection groove 33 developed on the plane has a substantially U-shaped track, the ball 3 accommodated in the ball deflection groove 33 reverses its rolling direction. Then, it enters the unloaded straight groove 32 of the moving block 2 facing the upper surface of the track rail 1. In addition, the ball 3 traveling in the no-load straight groove 32 enters the ball deflection groove 33 on the opposite side and reverses the rolling direction again, and then the load straight line between the rolling groove 10 of the track rail 1 and the moving block 2. It enters between the grooves 31. At this time, the ball 3 enters the space between the track rail 1 and the moving block 2 so as to climb down the concave curved surface 10a of the rolling groove 10 from the side, and as the ball deflection groove 33 gradually becomes shallow, no load is applied. Transition from state to load state.

  The ball 3 circulates in the track groove 30 of the moving block 2 in this way, and accordingly, the moving block 2 can move continuously along the track rail 1 without interruption.

  Considering the ease of forming the track groove 30 with respect to the moving block 2, as shown in FIG. 1, the moving block 2 is fixed to the block body 4 and both front and rear end faces in the moving direction of the block body 4. And a pair of end plates 5. That is, the load linear groove 31 and the no-load linear groove 32 constituting the track groove 30 are formed in the block body 4, and the ball deflection groove 33 is formed in each end plate 5. In FIG. 4, a boundary between the block body 4 and the end plate 5, that is, a divided section of the track groove 30 is indicated by a pair of two-dot chain lines A and B. A region sandwiched between these two-dot chain lines A and B is the block body 4, and a region outside these two-dot chain lines is the end plate 5. As is apparent from FIG. 4, the track groove 30 is divided into a linear region composed of the load linear groove 31 and the no-load linear groove 32 and a curved region composed of the ball deflection groove 33, and the linear region is formed in the block body. A curved region is formed in the end plate.

  FIG. 5 is a front view showing a contact surface of the end plate 5 with the block body 4. A pair of ball deflection grooves 33 constituting the track grooves 30 are formed on the end plate 5. Further, at the end of the ball deflection groove 33 corresponding to the load straight groove 31, a seal protrusion 35 is formed which enters the rolling groove 10 of the track rail 1 and minimizes the gap between the end plate 5 and the track rail 1. Has been. Since each ball deflection groove 33 is open toward the end surface of the block body 4, the end plate 5 provided with the ball deflection groove 33 can be easily manufactured by molding. For example, it can be manufactured using injection molding of synthetic resin, metal injection molding (MIM molding), or compression molding with metal powder (sintered alloy). The end plate 5 is fixed to the end surface of the block main body 4 with bolts 50. However, when the end plate 5 is made of synthetic resin, it is difficult to manage the tightening torque of the bolt 50. The end plate 5 is preferably made of metal from the standpoint of securing the straight guide device and improving the reliability of the linear guide device.

  On the other hand, FIG. 6 is a front view of the block body 4 observed from the longitudinal direction of the load straight groove 31. As a result of forming the ball deflection groove 33 in the end plate 5 and forming only the load linear groove 31 and the no-load linear groove 32 in the block main body 4, the block main body 4 has a longitudinal direction of the load linear groove 31. The same cross-sectional shape is continuous along the line. Further, an auxiliary curved surface portion 34 is provided on the end surface of the block body 4 so that the load linear groove 31, the end portion, and the end portion of the no-load linear groove 32 are smoothly connected. Is opposed to the ball deflection groove 33 of the end plate 5. This prevents occurrence of a situation in which the ball 3 rolling inside the ball deflection groove 33 is caught with respect to the end of the load straight groove 31 or the end of the no-load straight groove 32, and the ball inside the track groove 30 is prevented. 3 can be facilitated.

  As described above, since the block body 4 has the same cross-sectional shape along the longitudinal direction of the load straight groove 31, when the block body 4 is manufactured from a steel material, plastic working such as die forging or drawing is performed. It is possible to provide the block main body 4 with the loaded straight groove 31 and the unloaded straight groove 31 without using cutting or grinding.

  In particular, if the block main body 4 is manufactured using die forging, the load linear groove 31, the no-load linear groove 32, and the auxiliary curved surface portion 34 can be formed simultaneously with respect to the block main body 4. It can be made accurate and the processing accuracy of the block body 4a can be improved. Further, by using a hermetically sealed mold and performing the forging process as a cold process, the processing accuracy of the load linear groove 31, the no-load linear groove 32, and the auxiliary curved surface portion 34 can be further improved.

  The die forging process of the block body 4 may be a multistage process. That is, after several die forging processes, the shape of the block body 4 is gradually created from the steel rod, and the target block shape 4 is obtained by the final stage processing. In this way, through several stages of die forging, it is possible to further improve the processing accuracy of the block main body 4a and achieve smooth circulation of the balls 3 in the track grooves 30.

  In addition, such die forging can be performed by cold working to suppress changes in the dimensional accuracy of the block body 4 after processing. In this respect as well, the high-precision load linear groove 31 and the no-load straight groove 32 can be provided in the block body 4. Furthermore, if the die forging process is a multi-stage process, and the workpiece that becomes the block body 4 is continuously subjected to several stages of die forging without cooling between the processes, the work itself generates heat by forging in each process. Therefore, the deformation resistance of the workpiece is reduced, and it is possible to obtain the same effect as warm working.

  After the forging process, when the processing accuracy of the load linear groove 31, the no-load linear groove 32 and the auxiliary curved surface portion 34 is not sufficiently obtained, a sizing process using a die is performed to correct the block body 4, Ensures machining accuracy of loaded straight grooves and unloaded straight grooves. A mold that matches the final shape of the block body 4 is prepared in advance for the sizing process.

  Finally, the tapped holes 24 are formed on the mounting surface 23 of the movable body, and the tapped holes into which the fixing bolts of the end plate 5 are screwed are formed on both end surfaces in the moving direction. Ends.

  On the other hand, the block main body can be manufactured not only by the die forging process described above but also by a drawing process. In the drawing process, a die body is used to cold-draw the steel material to obtain the block body 4 in which the shape of the die is transferred to the steel material and the load linear groove 31 and the unloaded linear groove 32 are formed by plastic working. It becomes possible. At this time, by performing multi-stage drawing processing on the steel material, the cross-sectional shape of the steel material can be gradually decreased, and the load linear groove 31 and the no-load linear groove 32 can be provided in the block body 4 with high accuracy. .

  Thus, if the shape of the block body 4 is adjusted by drawing and the load linear groove 31 and the no-load linear groove 32 are provided to the block body 4 at the same time, the auxiliary curved surface portion 34 is formed on the end surface of the block body 4. Form. For the formation of the auxiliary curved surface portion 34, any of forging, cutting or grinding may be used.

  As described above, the moving block 2 is divided into the block main body 4 and the pair of end plates 5, and the block main body 4 having the load linear grooves 31 and the no-load linear grooves 32 is formed by die forging or drawing. On the other hand, if the end plate 5 is also formed using a mold, the processing time is shortened compared to the case where the track groove 30 is formed on the moving block 2 by using cutting or grinding. It becomes possible to do. Accordingly, the productivity of the moving block 2 is improved, and the linear guide device can be supplied to the consumer at a low cost.

  In addition, the shape of the die used for forging and the die used for drawing are transferred to the block body 4 to form the load linear groove 31 and the no-load linear groove 32, so that these grooves can be formed with high accuracy. Thus, the infinite circulation of the ball 3 in the track groove 30 can be facilitated, and as a result, the linear reciprocation of the moving block 2 relative to the track rail 1 can be performed smoothly.

It is front sectional drawing which shows an example of the linear guide apparatus to which this invention is applied. It is front sectional drawing of the linear guide apparatus shown in FIG. It is an enlarged view which shows the detail of the rolling groove | channel of the ball | bowl formed in the track rail. It is a figure which shows a mode that the track groove of the movement block was expand | deployed on the plane. It is a front view which shows an end plate. It is a front view which shows a block main body.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Track rail, 2 ... Moving block, 3 ... Ball, 4 ... Block main body, 5 ... End plate, 10 ... Rolling groove, 20 ... Horizontal web, 21 ... Flange part, 30 ... Track groove, 31 ... Load linear groove 32 ... No-load straight groove, 33 ... Ball deflection groove

Claims (6)

The track rail is formed in a substantially rectangular cross-section, and each side surface has a ball rolling groove arranged along the longitudinal direction, a horizontal web, and a pair of flange portions projecting from the horizontal web. A moving block that is formed in a channel shape with a guide groove and is assembled to a track rail loosely fitted in the guide groove via a large number of balls.
The moving block has a track groove in which the ball circulates infinitely and the entire area is opened toward the track rail;
The track groove includes a load straight groove disposed on an inner surface of the flange portion of the moving block so as to face the ball rolling groove of the track rail, and the load straight line with respect to a lateral web or the flange portion of the moving block. A non-load linear groove disposed in parallel with the groove, and a ball deflection groove that communicates and connects the load linear groove and the no-load linear groove,
The moving block is fixed to the metal block main body in which the load linear groove and the no-load linear groove of the track groove are simultaneously formed by plastic working, and the front and rear end surfaces in the moving direction of the block main body, and A linear guide device comprising a pair of end plates each having a ball deflection groove among track grooves . The ball deflection groove of the end plate is open toward the end surface of the block body, and the auxiliary curved surface portion that faces the ball deflection groove and connects the load linear groove and the no-load linear groove to the end surface of the block body. The linear guide device according to claim 1, wherein the linear guide device is formed. The linear guide device according to claim 2, wherein the end plate is made of a sintered alloy. 2. The method of manufacturing a linear guide device according to claim 1, wherein the block main body is formed by die forging, and the loaded linear groove and the unloaded linear groove are provided in the moving block during the die forging. A method for manufacturing a linear guide device. 3. The method of manufacturing a linear guide device according to claim 2, wherein the block main body is formed by die forging, and the load linear groove, the no-load linear groove, and the auxiliary curved surface portion are moved simultaneously during the die forging. The manufacturing method of the linear guide apparatus characterized by the above-mentioned. 2. The method of manufacturing a linear guide device according to claim 1, wherein the block main body is formed by a drawing process using a die, and the load linear groove and the no-load linear groove are provided in the moving block during the drawing process. A method for manufacturing a linear guide device.

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