JP4677896B2 - Rack cover mounting structure - Google Patents

Description

  The present invention relates to a rack cover mounting structure in which a rack cover that covers a meshing portion of a rack and a pinion is mounted on a side surface of the rack.

Conventionally, when a self-propelled carriage traveling on a conveyance path supports and conveys an object such as a work, a rack extending along the conveyance path is provided, and the self-propelled carriage side is rotated by a motor and meshes with the rack. 2. Description of the Related Art A cart traveling device in a transport device provided with a pinion is known (see Patent Document 1 below).
Japanese Examined Patent Publication No. 6-71688 (see claims, FIGS. 1 to 3)

  By the way, in the cart travel device in the transport device as described above, a rack and a pinion are used as a drive mechanism for moving the self-propelled cart, and such a meshing portion of the rack and the pinion has a mesh on the transport cart. If foreign matter such as welding spatter accumulates during machining operations such as welding to other workpieces, it will hinder the traveling of the self-propelled carriage.

  Therefore, it is conceivable to protect the meshed portion of the rack and the pinion by covering them with, for example, a plate-shaped rack cover along the extending direction of the rack.

  In this case, in order to attach the rack cover to the side surface of the rack, for example, screws are used to fasten and fix, but at that time, it is necessary to add a new screw hole to the side surface of the rack that is normally used as a standard part on the market. There is a problem that the cost and the construction period are excessive.

  Therefore, an object of the present invention is to eliminate the need for additional work such as a new attachment screw hole for the rack when the rack cover is attached to the side surface of the rack.

The present invention provides a rack cover mounting structure in which a rack cover that covers a tooth portion of a rack that meshes with a pinion is mounted on a side surface of the rack, and is provided in the positioning pin insertion hole provided in a rack mounting seat to which the rack is mounted. A positioning pin for positioning the rack with respect to the rack mounting seat is inserted through the through-hole, and a screw hole is provided at the end of the positioning pin on the rack side, and aligned with the screw hole. A screw insertion hole is provided in the rack cover, a screw is inserted from the screw insertion hole and fastened to the screw hole of the positioning pin, and the rack is positioned along a horizontal movement direction of a workpiece positioning device that positions and supports the workpiece. The pinion is extended and driven to move the workpiece positioning device along the extending direction of the rack. Is adapted to be sintered, the rack cover is the most important feature that covers the meshing portion between the rack and the pinion from above.

According to the present invention, a screw hole is provided in the positioning pin for positioning when the rack is attached to the rack mounting seat, and the rack cover is attached to the rack using this screw hole. Therefore, it is possible to use a standard rack of commercially available standard parts, and to prevent an increase in cost and work period.
Further, a rack provided to extend along the horizontal movement direction of the workpiece positioning device, the meshing portion between the pinion drivingly connected to move along the workpiece positioning device in the extension direction of the rack, the upper by the rack cover By covering and protecting from above , accumulation of foreign matters such as dust and welding spatter on the meshing portion can be prevented, and the operation of the gear transmission mechanism composed of the rack and the pinion can be normally performed.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a cross-sectional view taken along the line AA of FIG. 2, showing a rack cover mounting structure according to an embodiment of the present invention, and FIG. A pinion 43 is engaged with the tooth portion 40a of the rack 40 extended in the vertical direction in FIG. As such a gear transmission mechanism comprising the rack 40 and the pinion 43, for example, as shown in FIG. 4 to be described later, the workpiece positioning device 1 installed on the table 10 is provided along a pair of moving rails 37, 37. Used when moving. The workpiece positioning device 1 is used on an automobile body assembly line, and details thereof will be described later.

  As shown in FIG. 2, the rack 40 is mounted on a rack rail 41 as a rack mounting seat by a plurality of rack mounting portions 200 set along the extending direction (horizontal direction). As shown in FIG. 3 which is a BB cross-sectional view of FIG. 2, the rack mounting portion 200 is provided with a screw hole 41a in the upper part of the rack rail 41, and bolts are inserted into the rack 40 corresponding to the screw hole 41a. A hole 40b is provided, and a hexagon socket head bolt 201 as a fixture is inserted from the bolt insertion hole 40b and fastened to the screw hole 41a.

  The bolt insertion hole 40b of the rack 40 includes a head insertion recess 40d for inserting the head 201b of the hexagon socket head bolt 201 into the upper part of the screw portion insertion hole 40c having substantially the same diameter as the screw portion 201a of the hexagon socket head bolt 201. , And the head 201b is inserted into the head insertion recess 40d so that the surface of the head 201b corresponds to the upper surface of the rack 40 in FIG. It becomes.

  The rack cover 203 is attached to the upper surface in FIG. 3 opposite to the rack mounting seat 41 of the rack 40 described above. The rack cover 203 is attached to the rack attachment portions 200 at both the upper and lower ends in FIG. It is attached at a cover attachment portion 205 between each adjacent rack attachment portion 200.

  As shown in FIG. 1, the cover mounting portion 205 is provided with a through hole 40e in the rack 40 and a positioning pin insertion hole 41b in the rack rail 41 corresponding to the through hole 40e, and the through hole 40e and the positioning pin are inserted. A knock pin 207 as a positioning pin is inserted into the hole 41b from the through hole 40e side.

  The knock pin 207 inserted as described above has an end surface on the rack 40 side that is substantially flush with the side surface of the rack 40 described above, and a cover mounting screw hole 207a is provided on the end surface of the knock pin 207. ing. Corresponding to the screw hole 207a, the rack cover 203 is provided with a tapered hole 203a into which the head 209a of the countersunk screw 209 fastened to the screw hole 207a is inserted. The countersunk screw 209 is inserted into the taper hole 203 a of the rack cover 203 and fastened to the screw hole 207 a of the knock pin 207, so that the rack cover 203 is attached to the rack 40.

  At this time, the knock pin 207 is connected to the through hole 40e of the rack 40 and the positioning pin insertion hole 41b of the rack rail 41 by an appropriate frictional force, and therefore the rack cover 203 is interposed via the knock pin 207. To be attached to the rack 40.

  The cover mounting portion 205 for setting the knock pin 207 is set at an appropriate position along the vertical direction in FIG.

  The rack cover 203 attached to the side surface of the rack 40 in this way is provided with a bent portion 203c that bends upward in the vicinity of the tooth portion 40a from the fixing portion 203b that adheres and fixes to the side surface of the rack 40. The engagement portion 211 between the tooth portion 40a of the rack 40 and the pinion 43 is covered from above by the portion 203c.

  In this way, the bent portion 203c of the rack cover 203 covers and protects the meshing portion 211 between the tooth portion 40a of the rack 40 and the pinion 43 from above, so that foreign matter such as dust and welding spatter on the meshing portion 211 is protected. Accumulation can be prevented, and the gear transmission mechanism composed of the rack 40 and the pinion 43 can be operated normally.

  At this time, in this embodiment, in order to attach the rack cover 203 to the rack 40, the screw hole 207a provided in the knock pin 207 for positioning the rack 40 to the rack rail 41 is used.

  The through hole 40e provided in the rack 40 for inserting the knock pin 207 is normally used as a commercially available standard part in the same manner as the bolt insertion hole 40b provided in the rack 40 for attaching the rack 40 to the rack rail 41. The rack 40 is provided in advance. Therefore, in order to attach the rack cover 203 to the side surface of the rack 40, it is not necessary to newly add a mounting portion such as a screw hole to the rack 40, and the cost and construction period are not required. Can be prevented from increasing.

  Further, the hexagon socket head cap bolt 201 which is a fixing tool for attaching the rack 40 to the rack rail 41 is covered with a fixing portion 203 b of the rack cover 203 in a state where the rack cover 203 is attached to the rack 40. For this reason, since the hexagonal hole 201c as a tool insertion recessed part formed in the surface of the head 201b of the hexagonal socket head bolt 201 is also covered with the fixing part 203b, entry of foreign matters such as dust into the hexagonal hole 201c is prevented. can do.

  As a result, a hexagon wrench as a tool can be easily inserted into the hexagon hole 201c when the rack 40 is further removed from the rack rail 41 with the rack cover 203 removed from the rack 40, such as during equipment inspection. The removal work can be easily performed.

  In addition, as a fixing tool which fixes the rack 40 to the rack rail 41, the recessed part which inserts a tool in the head surface of a volt | bolt should just be formed not only in the hexagon socket head bolt 201.

  The workpiece positioning apparatus 1 shown in FIG. 4 has a positioning jig 100 at the tip, and as shown in FIGS. 5 and 6, a pair of conveyance units arranged (laid) in parallel on a vehicle body assembly line of an automobile. It is disposed on a base plate 3 that is slidable along the rails 2 and 2. In FIG. 6, the transport rails 2 and 2 are not shown.

  Here, four workpiece positioning devices 1 are arranged on each base plate 3, and each of these workpiece positioning devices 1 is positioned and supported by an engine complete 4 and a rear member 5 (workpiece) that are equivalent to one vehicle. It moves along the rails 2 and 2 for conveyance so that it may become an appropriate position, and the engine complete 4 and the rear member 5 are positioned and supported by the work positioning device 1. Then, the workpiece positioning device 1 is sequentially conveyed to each process such as an assembly process or a welding process provided in the assembly line. Specifically, the workpiece is supported and conveyed from the previous process to the subsequent process between adjacent processes.

  The four base plates 3 on which the workpiece positioning device 1 is placed are connected by a connecting rod 6 disposed (laid) between the pair of conveying rails 2 and 2 to constitute one device unit, and illustration is omitted. By being driven and controlled by the drive control unit, the workpieces can be reciprocated freely between the workpiece machining steps for performing various types of machining on the workpiece along the transport rails 2 and 2. The connecting rod 6 is, for example, a hollow pipe having a substantially rectangular cross section, and is fixed to the lower surface of each base plate 3 by fastening means such as bolts and nuts.

  Note that below the transfer rails 2, 2, rail supports 7, 7 for supporting the transfer rails 2, 2 are fixed on the floor.

  As shown in FIG. 4, the workpiece positioning device 1 includes a workpiece positioning jig 100 that positions and supports the engine complete 4 or the rear member 5, and two sets of arms 8 that have the positioning jig 100 attached to the tip portion. 8 and the positioning jig 100 attached to the distal ends of the arms 8 and 8 so that the arms 8 and 8 can be opened and closed with the bases 8a of the arms 8 and 8 being centered. Is engaged with the engaged part of the engine complete 4 and the rear member 5 to an engaged position where the arms 8, 8 are opened outward, and the arms 8, 8 are closed inward from the engaged position. The entire workpiece positioning mechanism section 9 including the arm opening / closing means arranged at each position and the positioning jig 100, the arms 8, 8 and the arm opening / closing means is connected to the engine complete Alternatively, an elevating unit that moves toward and away from the rear member 5 and a moving unit that moves the work positioning mechanism 9 and the table 10 on which the elevating unit is placed to a position where the engine complete 4 or the rear member 5 is positioned and supported. And.

  The positioning jig 100 includes a first positioning arm 101 extending in the X direction orthogonal to the Y direction and the Z direction in FIG. 4 and the Y direction from both sides of an appropriate position in the longitudinal direction of the first positioning arm 101. A second positioning arm 103 that extends and a positioning pin 105 as a protrusion that extends upward (in the Z direction) from the intersection of the positioning arms 101 and 103 are used to position the workpiece with respect to the workpiece. Do.

  As shown in FIG. 4, the arms 8, 8 are composed of two sets of arms 8, 8 that are shaped like a dogleg when viewed from the workpiece transfer direction (Y direction). Each set of arms 8 and 8 includes two arms, a first arm 8A and a second arm 8B. The first arm 8 </ b> A and the second arm 8 </ b> B are movably attached to an arm attachment plate 13, which is one of the components constituting the workpiece positioning mechanism section 9 described later.

  That is, the first arm 8A is movable about the support shaft 14 by attaching the base end portion 8a to the support shaft 14 fixed to the arm mounting plate 13 so as to be rotatable. The second arm 8B is movable around the shaft 16 by attaching the base end portion 8a to the shaft 16 fixed between the arm mounting plate 13 and the arm support plate 15 connected thereto. It is said.

  Further, the distal end portions 8b of the first arm 8A and the second arm 8B are both rotatable with respect to a support shaft 17 attached to the positioning jig support member 12 at a predetermined interval. Therefore, the arm 8 composed of the two first arms 8A and the second arm 8B is a so-called parallel link mechanism, and the positioning jig support member 12 attached to the tip 8b is always kept in a horizontal state. At the same time, the tip of the positioning pin 105 in the positioning jig 100 fixed to the positioning jig support member 12 is always kept upward.

  The arm opening / closing means includes a link member 18 in which one end 18a is connected to a middle position of the distal end portion 8b and the base end portion 8a of the first arm 8A, and an elevating member 19 in which the other end 18b of the link member 18 is connected, An elevating member drive mechanism that opens and closes the first arm 8A connected to the link member 18 by moving the elevating member 19 up and down to rotate the link member 18 connected to the elevating member 19. It consists of.

  The link member 18 is movable around the support shaft 20 by attaching one end 18a thereof to a support shaft 20 fixed to a position near the base end portion 8a of the first arm 8A. Further, the link member 18 is movable around the support shaft 21 by attaching the other end 18b to the tip of the support shaft 21 fixed to the elevating member 19 so as to be rotatable.

  The elevating member drive mechanism section includes a first elevating drive motor 22 for moving the elevating member 19 up and down, and a pair of first pulleys 23 and 23 for transmitting the power of the first elevating drive motor 22. The first driving belt 24 hung between the first pulleys 23, 23, the first ball screw 25 rotating with one base pulley 23 fixed to the base end, and the lifting member 19 And a first nut member 26 that moves up and down along the first ball screw 25.

  The first lifting / lowering drive motor 22 is fixed to the lifting / lowering table 27 and transmits a rotational force via a first drive belt 24 hung between a pair of first pulleys 23, 23. By rotating the first ball screw 25 fixed to one pulley 23 in the forward and reverse directions, the first nut member 26 screwed into the first ball screw 25 is moved up and down, and the first The elevating member 19 fixed to the nut member 26 is moved up and down. The first raising / lowering driving motor 22 is constituted by, for example, a stepping motor, and the like, and allows the raising / lowering member 19 to be moved up and down to a desired position with high accuracy when instructed by a drive control unit.

  The first pulleys 23 and 23 and the first drive belt 24 are rotatably disposed inside the lifting table 27. The first ball screw 25 and the first nut member 26 are provided in a first guide column 28 having a quadrangular prism shape that is fixed vertically to the lifting table 27. Most of the first nut member 26 is covered with the first guide column 28, but one surface to which the lifting member 19 is attached protrudes outward. The first nut member 26 is formed with a screw portion (not shown) that is screwed with the first ball screw 25, and the first ball screw 25 is rotated so that the first nut screw 26 rotates. The nut member 26 is sent to the first ball screw 25 and moves up and down between the lower end position and the upper end position.

In the arm opening / closing means configured as described above, in the standby state (the state shown in FIG. 7) before positioning and supporting the engine complete 4 and the rear member 5, the two arms cross and the tips of the arms 8, 8 are crossed. The positioning jig 100 attached to the part is placed at a position inside the arms 8, 8. In other words, positioning jig 100 is positioned inside the front end portion 8b of the second arm 8B disposed outside, not in contact jig, etc. and used in each step are arranged on both sides of the workpiece positioning device 1 It is provided in the retracted position.

  In response to a command from the drive control unit in this standby state, the first lifting / lowering drive motor 22 is driven, and the first ball screw 25 is rotated via the first pulleys 23 and 23 and the first drive belt 24. Then, the first nut member 26 screwed into the first ball screw 25 is sent to the upper position (raised). At this time, the elevating member 19 fixed to the first nut member 26 also rises together. As the elevating member 19 is raised, the elevating member 19 is rotatably attached to the support shaft 21 fixed to the elevating member 19. The link member 18 is rotated about the other end 18b attached to the support shaft 21 in the direction indicated by the arrow D in FIG. 7, and the first arm 8A connected to the one end 18a is opened outward. Rotate to. When the first arm 8A is rotated so as to open outward, the second arm 8B connected to the positioning jig support member 12 fixed to the tip end portion 8b of the first arm 8A is also linked outward. Rotate together.

  Then, as shown in FIG. 4, the two sets of arms 8 and 8 are opened so as to largely flutter outward on the right side and the left side, and the positioning jig 100 attached to the distal end portion 8b of each arm 8 and 8 is The arms 8 and 8 are arranged further outward from the tip 8b. In a series of states in which the arms 8 and 8 are rotated, the positioning jig support member 12 always holds the positioning jig 100 directly above by the first arm 8A and the second arm 8B constituting the parallel link mechanism. Move while keeping level. Therefore, regardless of the opening angle of the arms 8, 8, the engine complete 4 and the rear member 5 can be positioned and supported in any state, and this one positioning jig can be used for workpieces of different sizes and shapes. Positioning and support can be performed only with the tool 100.

  As shown in FIG. 4, the elevating means moves the entire workpiece positioning mechanism portion 9 including the positioning jig 100, the arms 8, 8 and the arm opening / closing means toward and away from the engine complete 4 or the rear member 5. A second raising / lowering drive motor 31 for moving the workpiece positioning mechanism 9 up and down, and a pair of second pulleys 33 for transmitting the power of the second raising / lowering drive motor 31. , 33, a second drive belt 34 hung between these second pulleys 33, 33, a second ball screw 35 rotating with one base pulley fixed to one second pulley 33, The arm mounting plate 13 is fixed to one surface, and includes a second nut member 36 that moves up and down along the second ball screw 35.

  The second lifting / lowering drive motor 31 is fixed on the table 10 described above. The second raising / lowering drive motor 31 transmits a rotational force via a second drive belt 34 hung between a pair of second pulleys 33, 33, and is fixed to one of the second pulleys 33. By rotating the second ball screw 35 in the forward and reverse directions, the second nut member 36 screwed into the second ball screw 35 is moved up and down to be fixed to the second nut member 36. The entire workpiece positioning mechanism 9 is moved up and down. The second lifting / lowering drive motor 31 is a stepping motor, similar to the first lifting / lowering driving motor 22, and the work positioning mechanism 9 is moved to a desired position with high accuracy when instructed by the drive control unit. It can be moved up and down.

  The second pulleys 33, 33 and the second drive belt 34 are disposed in a case 39 provided at the lower end of a second guide column 38 having a quadrangular prism shape fixed vertically to the table 10. In the second guide column 38, the second ball screw 35 and the second nut member 36 are disposed. The second nut member 36 is formed with a threaded portion (not shown) that is screwed with the second ball screw 35, and the second nut screw 36 rotates so that the second nut The member 36 is sent to the second ball screw 35 and moves up and down between the lower end position and the upper end position.

  In the lifting means configured as described above, when the second lifting / lowering driving motor 31 is driven and the second ball screw 35 is rotated via the second pulleys 33 and 33 and the second driving belt 34. Then, the second nut member 36 screwed into the second ball screw 35 is sent up and down (moved up and down). Accordingly, the work positioning mechanism 9 having the arm mounting plate 13 fixed to the second nut member 36 is engaged with the standby position lowered to the lower end shown in FIG. 7 and the predetermined position shown in FIG. It will move up and down between positions.

  The moving means is for moving the table 10 on which the workpiece positioning mechanism 9 and the lifting / lowering means are placed to a workpiece support position for positioning and supporting the engine complete 4 or the rear member 5, and the table 10 is slidable. A pair of moving rails 37, 37, a rack rail 41 having the rack 40 mounted on the upper surface, a table moving motor 42 fixed to the table 10, and a table moving motor 42 are attached to the rack. 40 and a pinion 43 that moves the table 10 in mesh.

  The moving rails 37, 37 are provided continuously so as to bridge the four base plates 3, and are fixed on a rail base 44 fixed on the base plate 3. The rack rail 41 is provided in the vicinity of one of the moving rails 37 and is fixed on the rail base 3. The table moving motor 42 is fixed to the table 10, and rotates the pinion 43 protruding from the lower surface of the table 10 by meshing with the rack 40, thereby moving the table 10 along the moving rails 37, 37. Reciprocating. The table moving motor 42 is a stepping motor that can be controlled by the control unit.

  In the present embodiment, the table moving motor 42 may be driven to move each table 10 on which the workpiece positioning mechanism 9 and the lifting / lowering means are placed to at least the respective workpiece support positions. It is also possible to move 10 by gathering them at one position.

  Next, the operation of positioning and supporting the workpiece (engine complete 4 and rear member 5) by the workpiece positioning device 1 configured as described above and conveying the workpiece will be described.

  First, the table moving motor 42 is driven to rotate the pinion 43 that meshes with the rack 40, thereby moving the table 10 along the moving rails 37 and 37. The table 10 has a work positioning mechanism 9 provided on the table 10 until a position corresponding to a work support position corresponding to a position below the engine complete 4 and the rear member 5 set at the positions shown in FIGS. 5 and 6. Moved.

Next, the second lifting / lowering driving motor 31 is driven, and the second nut 36 is kept in a state where the arms 8 and 8 are kept closed from the standby state in which the arms 8 and 8 are closed in FIG. by raising and raises the workpiece positioning mechanism 9 to a position where it does not interfere with etc. around the jig.

Next, the first raising / lowering driving motor 22 is driven to raise the first nut member 26, thereby rotating the link member 18 described above, and the two sets of arms 8 and 8 in the closed state are shown in the figure. Open outward as shown at 4 .

  A plurality of positioning portions (first and second positioning arms 101 and 103 and positioning pins 105) in the positioning jigs 100 and 100 of the arms 8 and 8 are engaged portions of the engine complete 4 and the rear member 5. When the position is appropriately engageable, the second lifting / lowering drive motor 31 is driven again to raise the work positioning mechanism 9 and the positioning jig 100 positions and supports the engine complete 4 and the rear member 5. .

  After the engine complete 4 and the rear member 5 are positioned and supported by the workpiece positioning mechanism 9, the four base plates 3 connected by the connecting rod 6 by driving a drive source (not shown) are moved along the transport rails 2 and 2. Then, the engine complete 4 and the rear member 5 are transported to the next adjacent process (post-process). Forwarding after the workpiece transfer is performed by reversing the above-described operation, returning the arms 8 and 8 to the closed state, and forwarding the workpiece positioning mechanism 9 to the adjacent previous process (previous process) as a standby position. .

It is AA sectional drawing of FIG. 2 which shows the attachment structure of the rack cover concerning one Embodiment of this invention. It is a top view which shows the attachment structure of the rack cover of FIG. It is BB sectional drawing of FIG. It is a perspective view of the workpiece | work positioning device provided with the attachment structure of the rack cover of FIG. It is a side view which shows the state which supported and positioned the workpiece | work using two or more workpiece | work positioning devices of FIG. FIG. 6 is a plan view of FIG. 5. It is a front view of the workpiece | work positioning device in the standby state which the arm closed.

Explanation of symbols

40 Rack 40a Rack tooth portion 40e Rack through hole 41 Rack rail (rack mounting seat)
41 b Rack rail positioning pin insertion hole 43 Pinion 201 Hexagon socket head cap screw (fixing tool)
201b Hexagon socket head bolt head 201c Hexagon socket head bolt (Tool insertion recess)
203 Rack cover 203a Rack cover screw insertion hole (tapered hole)
207 Knock pin (positioning pin)
207a Screw hole of the knock pin for mounting the rack cover 209 Flat head screw for mounting the rack cover 211 Engagement part of the rack and the pinion

Claims (3)

In a rack cover mounting structure in which a rack cover that covers a tooth portion of a rack meshing with a pinion is mounted on a side surface of the rack, a positioning pin insertion hole provided in a rack mounting seat to which the rack is mounted is inserted into a through hole provided in the rack. , A positioning pin for positioning the rack with respect to the rack mounting seat is inserted therethrough, a screw hole is provided at an end of the positioning pin on the rack side, and the screw insertion hole is aligned with the screw hole. Is provided in the rack cover, a screw is inserted from the screw insertion hole and fastened to the screw hole of the positioning pin,
The rack is provided so as to extend along a horizontal movement direction of a workpiece positioning device for positioning and supporting the workpiece, and the pinion is drive-coupled to move the workpiece positioning device along the extension direction of the rack. The rack cover mounting structure is characterized in that the rack cover covers a meshing portion of the rack and the pinion from above .   The fixture for mounting and fixing the rack to the rack mounting seat is constituted by a bolt having a tool insertion recess on the end face of the head, and the head of this bolt enters the head insertion recess provided on the side of the rack. The rack cover mounting structure according to claim 1, wherein the rack cover covers a head portion of the bolt in a state of being mounted on the rack.   The rack cover mounting structure according to claim 2, wherein the bolt is a hexagon socket head cap screw.

Images