JP2005195076A - Flexible screw drive height adjuster - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a flexible screw drive height adjuster which is equipped with an expandable unit having a multi-stage sliding member, to make it possible to obtain a perfect stroke with the minimum magnitude. <P>SOLUTION: A servomotor, a drive gear connected to the servomotor to rotate, and a driven gear engaged with the drive gear are provided in a housing. A spiral groove is formed at the center of the driven gear. A flexible screw rising and falling with the servomotor drive by engaging with the spiral groove, and one end of which extends outside the housing via one side face of the housing is provided. The expandable unit containing a plurality of sliding members mutually slidable in the predetermined direction is connected to the housing. Out of a plurality of sliding members, the first sliding member is slidably located in the housing, and the other end of the flexible screw is fastened to the last sliding member. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a height adjusting device, and more particularly, to a flexible screw-driven height adjusting device that includes a telescopic unit having a multi-stage sliding member and can obtain a complete stroke with a minimum size.

  Industrial equipment, machinery, structures, household products, and the like are provided with a height adjusting device that can expand and contract in the vertical direction. An example of such a height adjusting device is disclosed in US Pat. No. 4,682,930 (Patent Document 1), which will be described with reference to FIG.

  As shown in FIG. 1, the height adjusting device includes a drive pulley (36) on a drive shaft of a motor (6) fixed to a fixed frame (1). The driving pulley (36) is connected to the driven pulley (31) via the timing belt (32), and thereby the driven pulley (31) is rotatably supported with respect to the fixed frame (1).

  A spline shaft (33) capable of moving in the axial direction with respect to the driven pulley (31) is inserted into the driven pulley (31). The spline shaft (33) is rotatably supported on the intermediate frame (7) by a bearing.

  A first nut (4) is fixed to the fixed frame (1), and the first screw (5) is coupled to the first nut (4) so that linear movement is possible while rotating.

  A second nut (8) is installed on the intermediate frame (7) so as to be able to rotate by a bearing. The second screw (9) is coupled to the second nut (8) so as to be linearly movable while rotating, and the second screw (9) is rotatably supported by the transfer frame (10). .

  Pulleys (34, 11, 12) are coupled to the spline shaft (33), the first screw (5), and the second screw (9), respectively, and the pulleys (34, 11, 12) are mutually connected by a timing belt (35). It is connected to.

  In the conventional height adjusting apparatus configured as described above, the driving force of the motor (6) rotates the spline shaft (33) via the driving pulley (36), the timing belt (32), and the driven pulley (31). The rotational force of the spline shaft (33) is applied to the first and second screws (11, 12) via the pulley (34) coupled to the spline shaft (33) and the pulleys (11, 12) interconnected by the timing belt (35). 5 and 9) are rotated simultaneously. Accordingly, the first and second screws (5, 9) are linearly moved simultaneously with the rotation by the first and second nuts (4, 8), respectively, thereby the chuck (3) fixed to the transfer frame (10). ) Can be transferred to a predetermined position.

However, such a conventional height adjusting device requires many components such as a nut, a screw, a spline shaft, and a pulley in order to move the intermediate frame (7) and the transfer frame (10) up and down. For this reason, the structure becomes complicated when two or more frames are provided to be extendable. Therefore, there is a problem that not only the overall size and weight increase, but also a considerably large load is applied to the fixed frame (1) while the system is operated, and the operational safety of the system is lowered.
US Pat. No. 4,682,930

  The present invention is intended to solve such problems of the prior art. Therefore, the object of the present invention is to stabilize the complete stroke while simplifying the coupling structure of the telescopic unit having a multi-stage sliding member. It is to provide a flexible screw-driven height adjustment device that can be obtained.

  Another object of the present invention is to provide a flexible screw-driven height adjustment device that allows the size of the device to be minimized when the telescopic unit is fully retracted.

  In order to achieve the above object, a flexible screw drive type height adjusting device according to the present invention comprises a housing; a servo motor provided in the housing; a drive gear connected to the servo motor for rotation; A driven gear having a spiral groove formed in the center thereof; a flexible screw that engages with the spiral groove and moves up and down by driving a servo motor; and a plurality of sliding members that are slidably coupled to each other in a predetermined direction; It consists of an expansion / contraction unit that can expand and contract in the predetermined direction in conjunction with a flexible screw.

  The flexible screw is composed of a coil spring.

  The first sliding member of the plurality of sliding members is slidably located in the housing, one end of the flexible screw extends to the outside of the housing, and the other end is fixed to the final sliding member of the plurality of sliding members. Is done.

  The sliding member is composed of a pipe whose upper and lower ends are opened, and the cross-sectional area of the pipe gradually decreases from the first pipe to the final pipe, and the pipe has a circular or polygonal cross section.

  The flexible screw drive type height adjusting device according to the present invention has a simple structure for connecting a motor and a flexible screw, and a connecting structure between sliding members adjacent to each other. There is an effect that the ratio of the maximum height to the minimum height can be increased. In addition, by using a flexible screw consisting of a coil spring with appropriate rigidity depending on the load of the gripping object, the device is protected by mitigating the impact caused by the load of the gripping object during operation. There is an advantage that it can bend and extend in either direction of the housing.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

  2 and 3 are cross-sectional views showing the flexible screw drive type height adjusting device according to the first embodiment of the present invention in a fully extended state and a completely contracted state, respectively.

  As shown in the figure, the hollow housing (50) has an upper end closed and a lower end opened, and a servo motor (60) is supported and installed inside the hollow housing (50) by a support frame (52).

  A drive gear (64) is coupled to the drive shaft (62) of the servo motor (60) extending downward, and the bush (66) of the drive gear (64) is attached to the support frame (52) by a bearing (68). Combined for rotation.

  A driven gear (74) meshing with the drive gear (64) is provided inside the housing (50), and the bush (76) of the driven gear (74) is also rotatable to the support frame (52) by the bearing (78). To join.

  The open end of the housing (50) is provided with an extendable unit (80) composed of a plurality of sliding members (81, 82, 83, 84) that can be extended and contracted. In this embodiment, the sliding member is composed of hollow pipes whose upper and lower ends are open, and the number of pipes is four.

  More specifically, the telescopic unit (80) can be pulled out into and out of the housing (50). The second, third and fourth pipes (82, 83, 84) are slidably inserted into the pipes. That is, the second pipe is accommodated in the first pipe, the third pipe is accommodated in the second pipe, and the fourth pipe is accommodated in the third pipe. For this reason, it has a telescopic structure in which the cross-sectional area gradually decreases from the first first pipe (81) to the final fourth pipe (84). The number of pipes can be variously changed according to the application field of the height adjusting device.

  A release prevention step (54) is formed along the circumference of the open end of the housing (50). The release prevention step (54) protrudes to the inside of the housing (50) by a predetermined length. It is in contact with the outer peripheral surface of the pipe (81). Further, a locking protrusion (81a) is formed on the outer peripheral surface of the upper end of the first pipe (81) so as to come into contact with the detachment prevention step (54) of the housing (50). The pipe (81) is prevented from completely coming out of the housing (50).

  Similarly, on the inner peripheral surface of the lower end of the first pipe (81) and the outer peripheral surface of the upper end of the second pipe (82) inserted into the first pipe (81), a separation preventing step (81b) and a locking projection ( 82a) is formed. That is, each pipe has a locking projection and a detachment prevention step at the upper end and the lower end, respectively.

  However, the lowermost fourth pipe (84) has only a locking projection (84a) on the outer peripheral surface of the upper end, and an object gripping means such as a vacuum cup (92) is coupled to the lower end thereof.

  The housing (50) is provided with a flexible screw (90) for receiving a driving force from the servo motor (60) and elevating and retracting the expansion / contraction unit (80).

  In this embodiment, a coil spring having a predetermined rigidity is used as the flexible screw (90).

  The flexible screw (90) is arranged coaxially with the expansion / contraction direction of the expansion / contraction unit (80), and penetrates the center of the driven gear (74).

  A spiral groove (not shown) corresponding to the spiral of the flexible screw (90) is formed on the central surface of the driven gear (74).

  One end of the flexible screw (90) extends to the outside of the housing (50) through one side of the housing (50), and the other end is fixed to the bottom surface of the lowermost (final) fourth pipe (84). At this time, in order to smoothly move the flexible screw (90), one or more rollers (94) for guiding a bending portion of the flexible screw (90) are installed in the housing (50). The

  When the driven gear (74) rotates forward and backward, the flexible screw (90) is lowered or raised by the spiral groove formed at the center of the driven gear (74). At this time, the lowermost fourth pipe ( The flexible screw (90) with the other end fixed to 84) must be constrained in rotational motion. This is because if the pipe (81, 82, 83, 84) and the flexible screw (90) are both rotatable, the flexible screw (90) will not move up and down or the mobility will be significantly reduced. Because.

  For this reason, the pipes (81, 82, 83, 84) should have a configuration that restricts the rotation. By including a groove (not shown) formed long in the expansion and contraction direction, and an anti-rotation protrusion (not shown) formed corresponding to the groove on the inner surface of the pipe adjacent to the upper side of each pipe, The sliding movement between the pipes is allowed, but the relative rotational movement is limited. Such a relative rotation limiting structure is a known technique, and other modifications can be applied to the height adjusting device of the present invention.

  Further, when the cross section of the pipe (81, 82, 83, 84) is polygonal, the relative rotation between the pipes is restricted by the shape itself, so that separate relative rotation restriction such as a groove and an anti-rotation protrusion is provided. No structure is necessary.

  As described above, the flexible screw (90) made of a spring has to be selected with an appropriate rigidity in consideration of the load of the object to be grasped, and the impact due to the load of the object to be grasped during operation. Functions to relax and protect the device. Also, since the flexible screw (90) can be bent, it can extend in any direction of the housing (50) depending on the installation conditions of the apparatus, and in some cases, it can be rotated around the outer surface of the housing (50). It can also be designed to do.

  The internal space provided in the flexible screw (90) can be used as a passage for an electric wire, a hydraulic hose, or a pneumatic hose if necessary.

  Hereinafter, the operation of the flexible screw drive type height adjusting apparatus according to the first embodiment of the present invention configured as described above will be described with reference to FIGS.

  When the servo motor (60) is driven to increase the stroke of the height adjusting device, the drive gear (64) coupled to the drive shaft (62) and the driven gear (74) meshed with the drive gear (64). Rotate.

  The flexible screw (90) engaged with the spiral groove of the driven gear (74) is lowered by the rotation of the driven gear (74), so that each pipe (81, 82, 83, 84) is in the housing (50). ) And the pipes adjacent to each upper side, the telescopic unit (80) extends.

  As shown in FIG. 2, when the height adjusting device is fully extended, a locking projection (81a) formed on the outer peripheral surface of the upper end of the first pipe (81) is formed on the lower end of the housing (50). Then, the pipe comes into contact with the separation prevention stage (54), and similarly, the engagement protrusion of each pipe comes into contact with and engages with the separation prevention stage of the pipe located adjacent to the upper side, thereby locking the pipe. Prevent withdrawal.

  When the servo motor (60) is driven in the opposite direction to the extended state, the rotational directions of the drive gear (64) and the driven gear (74) are also reversed, and the flexible screw (90) is a spiral groove of the driven gear (74). Will rise.

  As shown in FIG. 3, when the height adjusting device is completely contracted by raising the flexible screw (90), the flexible screw (90) extending outside the housing (50) The pipes (81, 82, 83, 84) are accommodated inside the housing (50), and the size of the apparatus can be reduced and maintained.

  When the flexible screw (90) is raised and lowered, the bending portion of the flexible screw (90) is guided by a number of rollers (94) to facilitate the movement.

  FIG. 4 is a perspective view showing a telescopic unit of a flexible screw drive type height adjusting device according to a second embodiment of the present invention, and FIG. 5 is a perspective view showing a state where the telescopic unit of FIG. 4 is completely contracted. It is.

  As shown in FIG. 4, the telescopic unit (110) according to the second embodiment includes a plurality of ring-shaped sliding members (111, 112, 113, 114, 115, 116) arranged coaxially up and down, On the lower surface of the other sliding members (111, 112, 113, 114, 115) excluding the final (lowermost in FIG. 4) sliding member (116), the sliding member adjacent to the next (lower side in FIG. 4) One or more support rods (120) are formed respectively.

  Although the number of sliding members in the second embodiment is six from the first to sixth sliding members (111, 112, 113, 114, 115, 116), the number varies depending on the application field of the height adjusting device. It can be changed.

  The first sliding member (111) at the uppermost end is located inside the housing (see FIG. 2), and is prevented from being detached from the housing by contacting the housing detachment preventing step, and the flexible screw (see FIG. 2). The other end is fixed to the lowermost sixth sliding member (116).

  One or more support bars (120) extending vertically downward from the lower surface of the first to fifth sliding members (111, 112, 113, 114, 115) are respectively a main body (121) having a predetermined diameter. The lower end of the main body (121) has an extended end (122) having a larger diameter than the main body (121) and formed in a step.

  A first sliding hole (112) into which the main body (121) of the support rod (120) of the first sliding member (111) is inserted into the second sliding member (112) adjacent to the lower side of the first sliding member (111). 112a), the diameter of the first through hole (112a) is larger than the diameter of the body (121) of the support rod (120) and smaller than the diameter of the extended end (122). This is because when the telescopic unit (110) is fully extended, the second sliding member (112) is separated from each other by being locked to the extended end (122) of the support rod (120) of the first sliding member (111). This is to prevent this.

  Then, the first through hole in which the main body (121) of the support rod (120) of the second sliding member (112) is inserted into the third sliding member (113) adjacent to the lower side of the second sliding member (112). A hole (113a) and a second through hole (113b) through which the extended end (122) of the support rod (120) of the first sliding member (111) can pass are formed. The diameter of the first through hole (113a) is larger than the diameter of the main body (121) of the support rod (120) and smaller than the diameter of the extended end (122), and the diameter of the second through hole (113b) is the extended end (122). ).

  A lower end of a support rod (120) of a fifth sliding member (115) adjacent to the upper side of the sixth sliding member (116) at the lowermost stage is fixedly coupled to the lowermost sixth sliding member (116), and the first to fourth sliding members (111, 112, 113, 114) is formed with a through hole (116a) in which the extended end (122) of the support rod (120) can be accommodated.

  Preferably, in consideration of the size and weight of the expansion / contraction unit (110), the external impact in the lateral direction when fully extended, etc., in this embodiment, the number of support rods (120) of the sliding member at each end is three. did.

  Further, the rotation of the sliding member and the flexible screw is restricted by the support rod (120) coupled to the sliding member at each stage when the flexible screw is raised and lowered.

  As shown in FIG. 5, when the telescopic unit (110) is completely contracted, the first to fifth sliding members (111, 112, 113, 114, 115) are stacked so as to overlap each other. The extended end (122) of the rod (120) is received in the through hole (116a) of the sixth sliding member (116).

  Refer to FIGS. 2 and 3 for the configuration of a servo motor, a drive gear, a driven gear, a flexible screw and the like for extending or contracting the extension unit according to the second embodiment of the present invention configured as described above. Thus, the description of the coupling structure and operation is omitted.

  In the above, the present invention has been described with a plurality of embodiments. However, the present invention is not limited to the above-described embodiments, and in the field to which the present invention belongs without departing from the gist of the present invention claimed in the scope of claims. Anyone with ordinary knowledge can make various modifications.

It is a front view which shows the conventional height adjustment apparatus schematically. 1 is a cross-sectional view illustrating a state in which a flexible screw drive type height adjusting device according to a first embodiment of the present invention is fully extended; FIG. FIG. 3 is a cross-sectional view showing a state where the flexible screw drive type height adjusting device of FIG. 2 is completely stored. It is a perspective view which shows the expansion-contraction unit of the flexible screw drive type height adjustment apparatus by 2nd Example of this invention. It is a perspective view which shows the state which the expansion-contraction unit of FIG. 4 stored completely.

Explanation of symbols

50 Housing 60 Servo motor 64 Drive gear 74 Driven gear 80 Telescopic units 81, 82, 83, 84 Sliding member 90 Flexible screw 92 Vacuum cup 94 Roller

Claims (11)

housing;
A servo motor provided in the housing;
A driving gear connected to the servo motor and rotating;
A driven gear meshing with the drive gear and having a spiral groove formed in the center thereof;
A flexible screw that engages with the spiral groove and moves up and down by driving the servomotor; and a plurality of sliding members that are slidably coupled to each other in a predetermined direction. A flexible screw drive type height adjustment device comprising an expansion / contraction unit capable of expanding and contracting in a direction.   The flexible screw drive type height adjustment device according to claim 1, wherein the flexible screw is a coil spring. A first sliding member of the plurality of sliding members is slidably located in the housing;
2. The flexible screw drive type according to claim 1, wherein one end of the flexible screw extends outside the housing, and the other end is fixed to a final sliding member of the plurality of sliding members. Height adjustment device. Each of the plurality of sliding members is composed of a pipe whose upper and lower ends are open,
The flexible screw drive type height adjusting device according to claim 3, wherein the pipe has a cross-sectional area that decreases sequentially from the first pipe to the final pipe.   The flexible screw drive type height adjusting device according to claim 4, wherein the telescopic unit is accommodated in the housing when the telescopic unit is completely contracted.   The flexible screw-driven height adjustment device according to claim 4, wherein the pipe has a circular cross section.   The flexible screw-driven height adjustment device according to claim 4, wherein the pipe has a polygonal cross section. The telescopic unit is composed of a plurality of ring-shaped sliding members,
Among the plurality of sliding members, each of the sliding members immediately before the final from the first sliding member is formed with one or more support rods extending toward the next sliding member adjacent thereto,
Of the plurality of sliding members, a first through hole into which the support rod of the previous sliding member adjacent to the first sliding member is inserted into each of the sliding member following the first sliding member to the final sliding member. The flexible screw drive type height adjusting device according to claim 3, wherein one or more are formed.   Of the plurality of sliding members, each of the following sliding members from the next sliding member after the first sliding member to the final sliding member is formed on a sliding member further before the previous sliding member adjacent thereto. The flexible screw drive type height adjusting device according to claim 8, wherein at least one second through hole through which the support bar can pass is formed. The support bar has a main body having a predetermined diameter, and an extended end having a larger diameter than the main body at a lower end of the main body,
The diameter of the first through hole is larger than the diameter of the main body of the support rod and smaller than the diameter of the extended end,
The flexible screw-driven height adjustment device according to claim 9, wherein a diameter of the second through hole is larger than a diameter of the expansion end.   The flexible screw-driven height adjustment apparatus according to claim 1, further comprising one or more rollers installed in the housing to guide movement of the flexible screw.

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