JP5573621B2 - Ball screw device and method for attaching seal member thereof - Google Patents

Description

  The present invention relates to a ball screw device and a method for attaching a seal member thereof, and is particularly suitable for a ball screw device that is used by attaching a seal member to an end portion in the axial direction of a ball screw nut.

  The ball screw device has a male ball screw groove on the ball screw shaft and a female ball screw groove on the ball screw nut. A ball (steel ball) is interposed between the female and male ball screw grooves, and the steel ball rolls smoothly. Rotation-linear motion is possible. If foreign matter intervenes between the ball and the male and female ball screw grooves, smooth rotation-linear motion cannot be secured. For example, a seal member is attached to the axial end of the ball screw nut, and the seal lip of the seal member is placed inside the male ball screw groove. There is also a ball screw device that contacts the outer shape of the ball screw shaft and prevents foreign objects from entering. In the following Patent Document 1, a ball screw device is described in which two or more seal members are attached to the end of the ball screw nut in the axial direction. Further, in Patent Document 1, for example, when two thin plate-like seal members are attached in the axial direction, the ball screw grooves of the ball screw shaft at the seal lip position of each seal member are out of phase. It is also described that each seal member is fixed to a ball screw nut in accordance with the phase.

JP 2002-364726 A

  By the way, in the ball screw device described in Patent Document 1, phase adjustment in the rotational direction of the seal member itself with respect to the ball screw shaft or the ball screw nut cannot be performed. For example, when a seal member is attached to a predetermined end surface in the axial direction of the ball screw nut, the phase between the seal lip of the seal member attached to the predetermined end surface in the axial direction of the ball screw nut and the ball screw groove of the ball screw shaft is constant by design. In some cases, the phases of both may be shifted due to manufacturing errors. In such a case, in order to obtain good contact between the outer shape of the ball screw shaft and the seal lip of the seal member, it is necessary to adjust the phase of the seal member itself with respect to the ball screw shaft or the ball screw nut. However, the ball screw device described in Patent Document 1 has no means for adjusting the phase of the seal member. Also, for example, when mounting two thin plate-like seal members, if the seal member close to the ball screw nut is the inner seal member and the seal member far from the ball screw nut is the outer seal member, the sealing effect of the inner seal member is confirmed. After adjusting the phase of the inner seal member while checking the sealing effect of the outer seal member, the means for fixing the respective seal members in a state after the phase adjustment even if trying to adjust the phase of the outer seal member There is no.

  The present invention has been made paying attention to the above problems, and even when two or more sealing members are attached to the end of the ball screw nut in the axial direction, the sealing effect of each sealing member is effective. It is an object of the present invention to provide a ball screw device and a seal member mounting method that can be reliably obtained.

  In order to solve the above-described problems, the ball screw device of the present invention has two or more seal members attached in the axial direction to the end of the ball screw nut in the axial direction, and the inner shape of the seal lip of each seal member is the outer shape of the ball screw shaft. The screw member for fixing each of the two or more sealing members to the ball screw nut, and the axial direction of the ball screw nut corresponding to each sealing member Each sealing member nut screw hole formed at a different position on the end face, and a thread portion of each sealing member screw member formed at a position facing each corresponding sealing member nut screw hole of each sealing member; The phase adjustment mounting hole for each seal member that is long in the rotation direction of the ball screw nut or the ball screw shaft and the ball screw among the adjacent seal members When the seal member close to the inner seal member is the inner seal member and the seal member far from the ball screw nut is the outer seal member, the screw member for the outer seal member is formed on at least the inner seal member and fixes the outer seal member to the ball screw nut. And a screw member insertion hole for the outer seal member that is long in the rotation direction of the ball screw nut or the ball screw shaft.

Further, the nut screw holes for the respective seal members are formed on the same circumference of the end surface in the axial direction of the ball screw nut, and these nut screw holes corresponding to the respective seal members are sequentially formed. .
In the ball screw device sealing method according to the present invention, when the two or more seal members are attached to the axial end of the ball screw nut, the inner seal member is adjusted by adjusting the phase in the rotational direction of the inner seal member. While confirming the sealing effect of the member, the screw portion of the inner seal member screw member is screwed into the inner seal member nut screw hole of the ball screw nut to fix the inner seal member to the ball screw nut, and then the outer seal member While confirming the sealing effect of the outer seal member by adjusting the phase in the rotational direction, the screw portion of the screw member for the outer seal member is screwed into the nut screw hole for the outer seal member of the ball screw nut, and the outer seal member is It is characterized by being fixed to a ball screw nut.

  Thus, according to the ball screw device of the present invention, each sealing member nut screw hole into which each sealing member screw member for fixing each of the two or more sealing members to the ball screw nut is screwed is provided for each sealing member. Are formed at different positions on the axial end face of the ball screw nut, inserted through the threaded portions of the screw members for the seal members, and provided with phase adjustment mounting holes for the seal members that are long in the rotation direction of the ball screw nut or the ball screw shaft. Each seal member is formed at a position facing each corresponding seal member nut screw hole, and the thread portion of the outer seal member screw member for fixing the outer seal member to the ball screw nut is inserted through the ball screw nut or the ball screw shaft. Since the screw member insertion hole for the outer seal member that is long in the rotational direction is formed in at least the inner seal member, each seal member is rotated. By adjusting the phase in the direction, each seal member screw member can be screwed into each seal member nut screw hole of the ball screw nut while fixing the seal effect of each seal member to fix each seal member. Thereby, the sealing effect of each sealing member can be obtained reliably.

Moreover, each nut screw hole for seal members is formed on the same circumference of the end surface in the axial direction of the ball screw nut, and the nut screw holes for seal members corresponding to the respective seal members are formed in order so that the nut screw holes for seal members are formed. It is easy to form and it is easy to adjust the phase of each seal member in the rotation direction.
Further, according to the seal member mounting method of the ball screw device of the present invention, the screw portion of the screw member for the inner seal member is checked while checking the sealing effect of the inner seal member by adjusting the phase in the rotation direction of the inner seal member. Is screwed into the nut screw hole for the inner seal member of the ball screw nut to fix the inner seal member to the ball screw nut, and then the sealing effect of the outer seal member is adjusted by adjusting the phase in the rotational direction of the outer seal member. While confirming, the screw portion of the outer seal member screw member is screwed into the outer screw member nut screw hole of the ball screw nut and the outer seal member is fixed to the ball screw nut. Therefore, two or more seal members are attached to the ball screw nut. Even in the case of multiple mounting at the axial end, it is possible to reliably obtain the sealing effect of each sealing member. Kill.

It is a longitudinal cross-sectional view which shows one Embodiment of the ball screw apparatus of this invention. It is an axial direction arrow directional view of the axial direction end surface of the ball screw nut of the ball screw apparatus of FIG. FIG. 3 is an axial arrow view of a state in which an inner seal member is attached to an axial end surface of the ball screw nut of FIG. 2. FIG. 4 is an axial direction view of the state where the outer seal member is attached to the inner seal member of FIG. 3.

Next, an embodiment of the ball screw device of the present invention will be described with reference to the drawings.
FIG. 1 is an explanatory view of the ball screw device of the present embodiment. In the figure, reference numeral 1 denotes a ball screw shaft, and reference numeral 2 denotes a ball screw nut. The ball screw shaft 1 has a male ball screw groove, the ball screw nut 2 has a female ball screw groove, and a plurality of balls 3 are formed between the male and male ball screw grooves. It is intervened. For example, when the ball screw shaft 1 is rotated while restricting the rotation of the ball screw nut 2, the ball screw nut 2 moves directly. At this time, since the ball 3 interposed between the male and female ball screw grooves rolls, a smooth rotation-linear motion is achieved.

  In the present embodiment, two (two) thin plate-like seal members 4 and 5 are attached to the right end surface of the ball screw nut 2 on the right end portion of the ball screw nut 2 in the axial direction. Among these, the seal member 4 closest to the ball screw nut 2, that is, the seal member 4 on the left side in the figure is defined as the inner seal member 4, and the seal member 5 closest to the inner seal member 4, that is, the seal member 5 in the center in the figure is outside. When the seal member 6 is further defined on the side opposite to the ball screw nut 2 of the outer seal member 5 as will be described later, the seal member 6 is defined as the outer and outer seal member 6. In this embodiment, the inner seal member 4 is fixed to the ball screw nut 2 with the inner seal member screw member 7, and the outer seal member 5 is fixed to the ball screw nut 2 with the outer seal member screw member 8, The member 6 is fixed to the ball screw nut 2 with a screw member 9 for outer and outer sealing members. An inner seal lip 10 is formed on the inner seal member 4, an outer seal lip 11 is formed on the outer seal member 5, and an outer outer seal lip 12 is formed on the outer outer seal member 6. The inner shapes of all the seal lips 10 to 12 of 4 to 6 come into contact with the outer shape of the ball screw shaft 1 to generate a sealing effect.

  2 shows an inner seal member nut screw hole 13 formed on the right end surface (axial end surface) of the ball screw nut 2 shown in FIG. 1 and an outer seal member for fixing the inner seal member 4 to the ball screw nut 2. 5 is an axial view of the nut screw hole 15 for the outer seal member formed on the right end surface (end surface in the axial direction) of the ball screw nut 2 in order to fix 5 to the ball screw nut 2. FIG. In this embodiment, the nut screw hole 13 for the inner seal member and the nut screw hole 15 for the outer seal member are the same type of screw holes formed at equal intervals on the same circumference. 2 are formed at equal intervals in the upper, lower right and lower left portions of FIG. 2, and the outer seal member nut screw holes 15 are formed in the lower, upper right and upper left portions of FIG. It shall be formed. That is, the nut screw holes 13 and 15 for the seal members 4 and 5 are formed at different positions on the end surface in the axial direction of the ball screw nut 2 corresponding to the seal members 4 and 5. Moreover, the nut screw holes 13 and 15 for the seal members for the seal members 4 and 5 are formed on the same circumference of the end surface in the axial direction of the ball screw nut 2, and the nut screw holes 13 and 15 for the seal members in order. The seal member nut screw holes 13 and 15 correspond to the seal members 4 and 5, respectively. By doing in this way, it is easy to form each nut screw hole 13 and 15 for seal members, and it is easy to adjust the phase to the rotation direction of each seal member 4 and 5 so that it may mention later. The nut screw holes 13 and 15 for the seal members 4 and 5 may be screw holes having different specifications.

  FIG. 3 is an axial arrow view of the inner seal member screw member 7 screwed into the inner seal member nut screw hole 13 and the inner seal member 4 fixed to the ball screw nut 2. In the inner seal member 4, the screw portion of the inner seal member screw member 7 is inserted into a position facing the inner seal member nut screw hole 13 and the phase of the inner seal member 4 in the rotational direction is adjusted. A total of three phase adjustment mounting holes 14 for the inner seal member that are long in the rotational direction of the ball screw nut 2 or the ball screw shaft 1 are formed. In addition, the inner seal member 4 has an outer seal member screw member insertion hole 16 that is long in the rotational direction of the ball screw nut 2 or the ball screw shaft 1 at a position facing the outer seal member nut screw 15 of FIG. Three are formed.

  When the inner seal member 4 is attached to the ball screw nut 2, the screw portions of the three inner seal member screw members 7 are inserted into the inner seal member phase adjustment mounting holes 14, and the inner seal member screw members are inserted. 7 is slightly screwed into the nut screw hole 13 for the inner seal member of the ball screw nut 2. In this state, the inner seal member 4 is rotated in the rotational direction of the ball screw nut 2 or the ball screw shaft 1 to adjust the phase, and the inner shape of the inner seal lip 10 of the inner seal member 4 is in good contact with the outer shape of the ball screw shaft 1. State When the phase adjustment is thus completed, the inner seal member screw member 7 is screwed into the inner seal member nut screw hole 13 and tightened to fix the inner seal member 4.

  FIG. 4 is an axial arrow view showing a state in which the outer seal member screw member 8 is screwed into the outer seal member nut screw hole 15 and the outer seal member 5 is fixed to the ball screw nut 2. In order to adjust the phase of the outer seal member 5 in the rotational direction, the screw portion of the outer seal member screw member 8 is inserted into the outer seal member 5 at a position facing the nut screw hole 15 for the outer seal member. A total of three phase adjustment mounting holes 18 for the outer seal member that are long in the rotational direction of the ball screw nut 2 or the ball screw shaft 1 are formed. Further, the outer seal member 5 has an outer through-hole 17 for accommodating the head of the inner screw member 7 or operating the inner screw member 7 at a position facing the inner screw member 7. The screw nut 2 or the ball screw shaft 1 is opened in the longitudinal direction.

  When the outer seal member 5 is attached to the ball screw nut 2, the inner seal member 4 is attached to the ball screw nut 2 as described above, and then the screw portions of the three outer seal member screw members 8 are connected to the outer seals. The outer seal member screw member insertion holes 16 are inserted through the member phase adjustment mounting holes 18, and the outer seal member screw members 8 are slightly screwed into the outer seal member nut screw holes 15 of the ball screw nut 2. In this state, the outer seal member 5 is rotated in the rotation direction of the ball screw nut 2 or the ball screw shaft 1 to adjust the phase, and the inner shape of the outer seal lip 11 of the outer seal member 5 is in good contact with the outer shape of the ball screw shaft 1. State When the phase adjustment is completed in this manner, the outer seal member screw member 8 is screwed into the outer seal member nut screw hole 15 and tightened to fix the outer seal member 5.

  Incidentally, the phase difference between the inner shape of the inner seal lip 10 of the inner seal member 4 and the inner shape of the outer seal lip 11 of the outer seal member 5 with the inner seal member 4 and the outer seal member 5 attached to the ball screw nut 2. Is a predetermined phase difference according to the axial distance between the inner seal lip 10 of the inner seal member 4 and the outer seal lip 11 of the outer seal member 5, the number of ball screw grooves of the ball screw shaft 1, and the leads. For example, if the number of ball screw grooves on the ball screw shaft 1 is 1, the lead is L, and the axial distance between the inner seal lip 10 of the inner seal member 4 and the outer seal lip 11 of the outer seal member 5 is x, the inner seal The phase difference φ between the inner shape of the inner seal lip 10 of the member 4 and the inner shape of the outer seal lip 11 of the outer seal member 5 is expressed by φ = (x / L) × 360 °.

  As described above, in the ball screw device and the seal member mounting method of the present embodiment, the inner seal member screw member 7 and the outer seal member screw for fixing the inner seal member 4 and the outer seal member 5 to the ball screw nut 2 are provided. The inner seal member nut screw hole 13 and the outer seal member nut screw hole 15 into which the member 8 is screwed are formed at different positions on the axial end surface of the ball screw nut 2 corresponding to the inner seal member 4 and the outer seal member 5, respectively. The inner seal member screw member 7 and the outer seal member screw member 8 are threaded through the threaded portions of the inner seal member and the ball screw nut 2 or the ball screw shaft 1 and the outer seal member. The position adjustment mounting hole 18 is provided in the inner seal member 4 and the outer seal member 5 with the corresponding inner seal member nut screw hole 13 and the outer seal member. The screw member 15 is formed at a position opposite to the nut screw hole 15 for the screw member, and the thread portion of the screw member 8 for the outer seal member for fixing the outer seal member 5 to the ball screw nut 2 is inserted, and the ball screw nut 2 or the ball screw shaft 1 is rotated. Since the screw member insertion hole 16 for the outer seal member that is long in the direction is formed in the inner seal member 4, the inner seal member 4 and the outer seal member are adjusted by adjusting the phase of the inner seal member 4 and the outer seal member 5 in the rotational direction. 5, the inner seal member screw member 7 and the outer seal member screw member 8 are respectively connected to the inner seal member nut screw hole 13 and the outer seal member nut screw hole 15 of the ball screw nut 2. Each of the inner seal member 4 and the outer seal member 5 can be fixed by screwing, whereby the inner seal member 4 and the outer seal member 4 can be fixed. The respective sealing effect of the sealing member 5 can be reliably obtained.

  Further, by adjusting the phase of the inner seal member 4 in the rotational direction, the screw portion of the inner seal member screw member 7 is inserted into the nut screw hole for the inner seal member of the ball screw nut 2 while confirming the sealing effect of the inner seal member 4. 13 to fix the inner seal member 4 to the ball screw nut 2 and then adjust the phase of the outer seal member 5 in the rotational direction to confirm the sealing effect of the outer seal member 5 while checking the sealing effect of the outer seal member 5. Since the screw portion of the member screw member 8 is screwed into the nut screw hole 15 for the outer seal member of the ball screw nut 2 and the outer seal member 5 is fixed to the ball screw nut 2, the inner seal member 4 and the outer seal member 5 are fixed. Even when multiple screws are attached to the axial end of the ball screw nut 2, the seals of the inner seal member 4 and the outer seal member 5 are used. Results can be obtained reliably.

  Further, as shown by a two-dot chain line in FIG. 1, when the outer outer seal member 6 is further attached to the side opposite to the ball screw nut 2 of the outer seal member 5, the outer outer seal is located at a different position on the axial end surface of the ball screw nut 2. Form a nut screw hole for the member, form a phase adjustment mounting hole for the outer and outer seal member at a position facing the nut screw hole for the outer and outer seal member of the outer and outer seal member 6, and also face the nut screw hole for the outer and outer seal member A screw member insertion hole for the outer and outer seal member is formed at the position of the inner seal member 4 and the outer seal member 5 to be inserted through the screw portion of the outer and outer seal member screw member 9, and the phase adjustment mounting hole for the outer and outer seal member The screw portion of the outer outer screw member 9 is inserted into the screw member insertion hole for the outer outer seal member, and the outer outer screw member 9 is screwed into the nut screw hole for the outer outer seal member; From a outer sealing member 6 and the phase adjustment in the rotational direction so as to hold the outside outer sealing member 6 to the ball screw nut 2, it is possible to reliably obtain the sealing effect of the outer outer seal member 6. In addition, by repeating this in sequence, even when two or more seal members are attached to the ball screw nut 2 in a multiple manner, the phase adjustment of each seal member is performed sequentially from the side closest to the ball screw nut 2 and fixed. The sealing effect of each sealing member can be reliably obtained.

  In the above embodiment, the inner seal member 4 is directly attached to the ball screw nut 2, and the outer seal member 5 is directly attached to the inner seal member 4. However, a member other than the seal member is interposed therebetween. For example, a holding member made of a thin metal plate for holding the seal member may be interposed. In any case, if the seal member close to the ball screw nut 2 is the inner seal member 4 and the seal member far from the ball screw nut 2 is the outer seal member 5, the present invention can be applied to all seal members.

1 is a ball screw shaft 2 is a ball screw nut 3 is a ball 4 is an inner seal member 5 is an outer seal member 6 is an outer outer seal member 7 is a screw member for an inner seal member 8 is a screw member for an outer seal member 9 is for an outer outer seal member Screw member 10 is inner seal lip 11 is outer seal lip 12 is outer and outer seal lip 13 is nut screw hole for inner seal member 14 is phase adjustment mounting hole for inner seal member 15 is nut screw hole for outer seal member 16 is for outer seal member Screw member insertion hole 17 is an outer through hole 18 is a phase adjustment mounting hole for an outer seal member

Claims (3)

  A ball screw device in which two or more seal members are mounted in the axial direction on the axial end of a ball screw nut and the inner shape of the seal lip of each seal member is in contact with the outer shape of the ball screw shaft, and the two or more seal members Screw member for each sealing member for fixing each to the ball screw nut, and nut screw hole for each sealing member formed at a different position on the axial end surface of the ball screw nut corresponding to each sealing member. The seal member is formed at a position facing the corresponding nut screw hole for each seal member, and is inserted through the screw portion of each seal member screw member and is long in the rotation direction of the ball screw nut or the ball screw shaft. Of the seal member adjacent to the phase adjustment mounting hole, the seal member close to the ball screw nut is the inner seal member, the ball screw When the seal member that is far from the outer seal member is used as the outer seal member, the screw portion of the outer seal member screw member that is formed on at least the inner seal member and that fixes the outer seal member to the ball screw nut is inserted and the ball screw nut or the ball screw shaft is inserted. And a screw member insertion hole for the outer seal member that is long in the rotation direction of the ball screw device.   The said nut screw hole for each seal member is formed on the same circumference of the axial direction end surface of a ball screw nut, and they were made into the nut screw hole for seal members applicable to each seal member in order. Ball screw device.   When attaching the two or more seal members to the axial end of the ball screw nut, the screw member for the inner seal member is checked while checking the sealing effect of the inner seal member by adjusting the phase in the rotational direction of the inner seal member. The outer seal member is screwed into the nut screw hole for the inner seal member of the ball screw nut to fix the inner seal member to the ball screw nut, and then the phase of the outer seal member in the rotational direction is adjusted. The screw portion of the outer seal member screw member is screwed into the nut screw hole of the outer seal member of the ball screw nut while confirming the sealing effect, and the outer seal member is fixed to the ball screw nut. 3. A method for attaching a seal member of the ball screw device according to 2.

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