Vehicle maintenance lift

Abstract

To provide a vehicle maintenance lift that can reduce the operating force required to unlock a swing arm that can lock the rotation of a second arm that is pivotally attached to the tip side of a slidable first arm so as to be horizontally rotatable.SOLUTION: A vehicle maintenance lift 1 comprises: a locking mechanism 50 having a locking gear 51 and a locking piece 52 and locking a rotation of a second arm 20 relative to a first arm 10; a link mechanism 60 consisting of a plurality of links connected to each other and capable of changing a posture thereof between a first posture in which the locking piece 52 engages with the locking gear 51 and a second posture in which the locking piece 52 moves away from the locking gear 51 and the engagement is released; a spring 70 provided between the first arm 10 and the link mechanism 60 and biasing the link mechanism 60 in the direction of the first posture; and a rotating knob 80 acting on a predetermined portion of the link mechanism 60 to change the link mechanism 60 from the first posture to the second posture against the biasing force of the spring 70.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to a vehicle maintenance lift having a swing arm. [Background technology]

[0002] Conventionally, vehicle maintenance lifts have been widely used, each of which includes a carriage that can be raised and lowered, and a swing arm that is pivotally attached to the carriage so as to be horizontally rotatable and has a vehicle receiving portion at its tip. One such vehicle maintenance lift has been proposed, in which the swing arm includes a base arm, a first arm that is slidably attached to the base arm in the arm longitudinal direction, and a second arm that is pivotally attached to the tip of the first arm so as to be horizontally rotatable (see, for example, Patent Document 1, etc.).

[0003] This prior art vehicle maintenance lift is equipped with a locking mechanism that has a locking gear provided at the base end of the second arm and a locking piece provided on the first arm that can engage and disengage with the locking gear, thereby locking the second arm from rotating relative to the first arm, and is capable of locking the second arm in a position where it has been horizontally rotated to a desired angle relative to the first arm. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] European Patent Application Publication No. 4169867 Summary of the Invention [Problem to be solved by the invention]

[0005] However, the vehicle maintenance lift of the above-mentioned prior art has a structure in which the locking piece is held in the locked state by being strongly biased toward the lock gear by a spring as a biasing member, and when unlocking, the locking piece is moved in the opposite direction to the lock gear by an external force. Therefore, there is a problem that the operator has to exert a heavy operating force when moving the locking piece against the biasing force of the biasing member.

[0006] The present invention has been made in consideration of the above-mentioned problems, and aims to provide a vehicle maintenance lift that can reduce the operating force required to unlock a swing arm in which a second arm is pivotally attached to the tip of a slidable first arm so that it can rotate horizontally and is lockable. [Means for solving the problem]

[0007] The vehicle maintenance lift according to the present invention is a vehicle maintenance lift comprising a carriage that can be raised and lowered, and a swing arm that is pivotally attached to the carriage so as to be horizontally rotatable and has a vehicle receiving portion at its tip, wherein the swing arm comprises a base arm, a first arm that is provided so as to be slidable in the arm longitudinal direction relative to the base arm, and a second arm that is pivotally attached to the tip side of the first arm so as to be horizontally rotatable, and the vehicle maintenance lift comprises a lock gear provided at the base end of the second arm, and a lock piece that is provided on the first arm so as to be able to engage and disengage with the lock gear, and the first arm of the second arm a link mechanism consisting of a plurality of links connected to each other, one end of which is supported by the first arm and the other end of which is connected to the lock piece, and which is capable of changing its position between a first position in which the lock piece engages with the lock gear and a second position in which the lock piece moves away from the lock gear and is disengaged; a biasing member provided between the first arm and the link mechanism for biasing the link mechanism in the direction of assuming the first position; and an operating member acting on a predetermined portion of the link mechanism for changing the link mechanism from the first position to the second position against the biasing force of the biasing member.

[0008] According to this configuration, the link mechanism is normally held in the first position by the biasing force of the biasing member, and the lock piece engages with the lock gear, so that the rotation of the second arm is reliably locked, ensuring safety. Meanwhile, by operating the operating member to change the link mechanism from the first position to the second position against the biasing force of the biasing member, the lock piece moves away from the lock gear and is released from engagement with the lock gear, so that the lock on the rotation of the second arm can be easily released with a small force. Therefore, it is possible to provide a vehicle maintenance lift that can be easily unlocked by reducing the operating force required to unlock the rotation of the second arm that is pivotally mounted on the tip side of the first arm of the swing arm so as to be horizontally rotatable.

[0009] The operating member extends in the thrust direction relative to the link mechanism.

[0010] With this configuration, the operating member extends in the thrust direction relative to the link mechanism (a direction parallel to the axial direction of each connecting shaft of the link mechanism), so the link mechanism can be changed from the first position to the second position by operating it in a direction different from the sliding direction of the first arm. In other words, if the operating member were extended in the radial direction relative to the link mechanism, the operating direction of the operating member would be the same as the sliding direction of the first arm, which could lead to the possibility of accidentally sliding the first arm when unlocking the second arm, but with the above configuration, it is possible to avoid accidentally sliding the first arm.

[0011] The thrust direction of the link mechanism is a horizontal direction perpendicular to the longitudinal direction of the arm.

[0012] With this configuration, the thrust direction of the link mechanism is horizontal (i.e., left-right relative to the swing arm) perpendicular to the arm longitudinal direction, so the operating member extends left-right relative to the swing arm. This reduces the height of the operating member on the swing arm inserted between the vehicle underside and the installation surface, making it possible to avoid interference between the operating member and the vehicle.

[0013] The operating member is a rotation operating member that rotates the link mechanism by a predetermined angle around an axis that extends in the thrust direction at a predetermined portion of the link mechanism.

[0014] With this configuration, because the operating member is a rotary operating member, the link mechanism can be changed from the first position to the second position by rotating it by a predetermined angle about an axis that extends in the thrust direction at a predetermined location on the link mechanism. With this configuration, because the sliding direction of the first arm and the operating direction of the operating member differ, it is possible to prevent the first arm from being erroneously slid when unlocking the second arm, thereby improving safety.

[0015] The rotation operation member is a rotation knob that is gripped by hand and rotated.

[0016] With this configuration, the rotation operating member is a rotation knob that is gripped and rotated by hand, so that the link mechanism can be easily changed from the first position to the second position by rotating it a predetermined angle around the axis. Also, the second arm will not be unlocked simply by the worker's hand or foot accidentally coming into contact with the rotation knob, preventing mistaken unlocking of the rotation of the second arm and improving safety.

[0017] Furthermore, in the link mechanism, when the operating member is displaced by a first phase width to one side from the dead point phase corresponding to the extension dead point of the link mechanism, positional change is restricted in the first position and the lock piece and the lock gear are engaged, and when the operating member is displaced by a second phase width larger than the first phase width from the dead point phase to the other side opposite to the one side, the engagement between the lock piece and the lock gear is released in the second position.

[0018] With this configuration, when the operating member is displaced from the dead center phase to one side by the first phase width, the link mechanism is restricted from changing its position in the first posture and the lock piece and the lock gear are engaged, so that the rotation of the second arm is securely locked and the locked state is maintained. On the other hand, when the operating member is operated to displace the operating member from the dead center phase to the other side by the second phase width, the engagement between the lock piece and the lock gear is released in the second posture, so that the lock on the rotation of the second arm can be easily and securely released by simply operating the operating member lightly.

[0019] The operating member also acts on a specific link connected to the lock piece to change the angle of connection with the lock piece.

[0020] With this configuration, the operating member acts on a specific link connected to the locking piece to change the connection angle relative to the locking piece, thereby changing the link mechanism from the first position to the second position with a small force. Also, because the operating member acts on a specific link connected to the locking piece, the operating member can be positioned closer to the tip of the first arm, ensuring a large sliding range for the first arm relative to the base arm. [Brief explanation of the drawings]

[0021] [Figure 1] 1 is a perspective view showing the overall configuration of a vehicle maintenance lift according to an embodiment of the present invention; [Figure 2] FIG. 2 is a perspective view showing the swing arm and its surroundings of the vehicle maintenance lift. [Figure 3] FIG. 10 is a perspective view showing the periphery of the swing arm in which the rotation angle of the second arm is changed. [Figure 4] FIG. 10 is another perspective view showing the periphery of the swing arm in which the rotation angle of the second arm is changed. [Figure 5] FIG. 10 is a side view showing the periphery of the locking mechanism in a locked state. [Figure 6] FIG. 10 is a side view showing the periphery of the locking mechanism during transition between a locked state and an unlocked state. [Figure 7]FIG. 10 is a side view showing the periphery of the locking mechanism in an unlocked state. [Figure 8] FIG. 10 is a plan view showing the periphery of the locking mechanism in a locked state. [Figure 9] 10 is a plan view showing the periphery of the locking mechanism during transition between a locked state and an unlocked state. FIG. [Figure 10] FIG. 10 is a plan view showing the periphery of the locking mechanism in an unlocked state. DETAILED DESCRIPTION OF THE INVENTION

[0022] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A vehicle maintenance lift according to an embodiment of the present invention will now be described with reference to the accompanying drawings.

[0023] <Configuration of vehicle maintenance lift 1> First, the configuration of a vehicle maintenance lift 1 according to an embodiment of the present invention will be described with reference to FIGS. 1 to 7. FIG. 1 is a perspective view showing the overall configuration of the vehicle maintenance lift 1. FIG. 2 is a perspective view showing the periphery of the swing arm 4 of the vehicle maintenance lift 1. FIG. 3 is a perspective view showing the periphery of the swing arm 4 with the rotation angle of the second arm 20 changed. FIG. 4 is another perspective view showing the periphery of the swing arm 4 with the rotation angle of the second arm 20 changed. FIG. 5 is a side view showing the periphery of the lock mechanism 50 in the locked state. FIG. 6 is a side view showing the periphery of the lock mechanism 50 in the midst of transition between the locked state and the unlocked state. FIG. 7 is a side view showing the periphery of the lock mechanism 50 in the unlocked state. FIG. 8 is a plan view showing the periphery of the lock mechanism 50 in the locked state. FIG. 9 is a plan view showing the periphery of the lock mechanism 50 in the midst of transition between the locked state and the unlocked state. FIG. 10 is a plan view showing the periphery of the lock mechanism 50 in the unlocked state.

[0024] The vehicle maintenance lift 1 is called a two-post lift or a portal lift, and is a vehicle maintenance lift that raises and lowers a vehicle to be maintained by supporting the vehicle at four points.

[0025] The vehicle maintenance lift 1 includes support columns 2, 2, carriages 3, 3, and swing arms 4, 4, 4, 4, 4.

[0026] 1, a pair of support pillars 2, 2 are erected on the floor of a vehicle maintenance workshop, sandwiching a vehicle (not shown) to be maintained therebetween. The support pillars 2, 2 are connected by a connecting beam 2a to form a gate-like structure as a whole.

[0027] The carriages 3, 3 are assembled so as to be able to move up and down along the support posts 2, 2. Each carriage 3 is adapted to be moved up and down by a hydraulic cylinder incorporated in the support post 2.

[0028] The swing arm 4 is pivotally attached to each carriage 3 so as to be horizontally rotatable, and has a vehicle support portion at its tip. Each swing arm 4 is a multi-joint swing arm comprising a base arm 5, a first arm 10, and a second arm 20.

[0029] The base arm 5 is an arm member whose base end is pivotally attached to the carriage 3 so as to be horizontally rotatable, and is also called a lift arm. Specifically, the base arm 5 is configured to include a base arm main body 5a and a slide body 5b.

[0030] The base arm body 5a is a square tubular steel member extending in the arm longitudinal direction A, and its base end is pivotally attached to the carriage 3 so as to be horizontally rotatable. The slide body 5b is a square tubular steel member extending in the arm longitudinal direction A like the base arm body 5a, and its base end is inserted into the inner periphery of the base arm body 5a so as to be slidable in the arm longitudinal direction A.

[0031] The first arm 10 is provided to the base arm 5 so as to be slidable in the arm longitudinal direction A. Specifically, the base end side of the first arm 10 is inserted into the inner periphery of the slider 5b of the base arm 5 and assembled so as to be slidable in the arm longitudinal direction A. The first arm 10 is formed in a rectangular cylindrical shape and includes an upper plate 10a, a lower plate 10b, and left and right side plates 10c, 10c.

[0032] The second arm 20 is pivotally attached to the tip side of the first arm 10 so as to be horizontally rotatable. Specifically, the second arm 20 comprises a base end member 20a and a tip end member 20b, and is integrally configured by overlapping and fixing the upper surface of the tip end member 20b near the base end to the lower surface of the base end member 20a near the tip in the arm longitudinal direction A. The base end member 20a is pivotally attached to the tip of the first arm 10 via a vertical rotation shaft 21 so as to be horizontally rotatable. A receiving metal 30 serving as a vehicle receiving portion is attached to the tip portion of the tip end member 20b in the arm longitudinal direction A.

[0033] The receiving metal 30 is configured to include a cylindrical base attached to the tip member 20b, an adjusting rack that has a receiving member at its upper end that abuts against a lift point such as a vehicle side sill and is movable up and down within the base, a guide member that guides the up and down movement of the adjusting rack, and a locking member that locks onto the adjusting rack at a predetermined up and down position to restrict its descent. However, the configuration of the receiving metal 30 is not limited to this.

[0034] The vehicle maintenance lift 1 further includes a locking mechanism 50, a link mechanism 60, a spring 70, and a rotation knob 80.

[0035] The lock mechanism 50 has a lock gear 51 and a lock piece 52, and is a mechanism that locks the rotation of the second arm 20 relative to the first arm 10.

[0036] Lock gear 51 is a gear member provided at the base end of second arm 20. Specifically, lock gear 51 has a gear portion formed with a large number of teeth on the outer periphery of an arc shape, and is disposed coaxially with rotation shaft 21 and fixed to second arm 20 (base end member 20a).

[0037] The lock piece 52 is a lock piece provided on the first arm 10 so as to be able to engage with and disengage from the lock gear 51. The lock piece 52 is a claw-shaped member having teeth that mesh with the gear portion of the lock gear 51, and is disposed opposite the lock gear 51. A slide portion 52a is provided integrally with the lock piece 52, and the lock piece 52 is able to slide freely in the arm longitudinal direction A between the upper plate 10a and the lower plate 10b of the first arm 10. As shown in FIG. 5, the link mechanism 60 is urged by the elastic urging force of the spring 70 and held in a forward position, so that the lock piece 52 is always engaged with the lock gear 51.

[0038] Link mechanism 60 is made up of a plurality of links connected to one another and is housed within first arm 10, with one end supported by first arm 10 and the other end connected to lock piece 52. Link mechanism 60 is capable of changing its position between a first position (see FIGS. 5 and 8) in which lock piece 52 engages with lock gear 51 and a second position (see FIGS. 7 and 10) in which lock piece 52 moves away from lock gear 51 and the engagement is released.

[0039] More specifically, the link mechanism 60 is composed of a first link 61 and a second link 62 that are connected to each other via a connecting shaft 61a. The connecting shaft 61a is disposed in a horizontal direction perpendicular to the longitudinal direction of the arm, and connects the first link 61 and the second link 62 to each other so that they can rotate freely.

[0040] The first link 61 is connected to the first arm 10 via a connecting pin 71. A rotating shaft 61b is provided inside the first arm 10, arranged in a horizontal direction perpendicular to the arm longitudinal direction A and spanning between the left and right side plates 10c, 10c, and the first link 61 is supported so as to be rotatable about the rotating shaft 61b. A connecting pin 71 is provided between the upper plate 10a and the lower plate 10b of the first arm 10, and the connecting pin 71 is inserted into a hole 61e opening in a plate-like end portion 61d provided on the base end side of the first link 61 in the arm longitudinal direction A, and the first link 61 and the first arm 10 are connected by engaging with each other.

[0041] A spring 70 is interposed around the outer periphery of the connecting pin 71 and between the first link 61 and the lower plate 10b of the first arm 10. Therefore, the plate-shaped end 61d of the first link 61 on the base end side in the arm longitudinal direction A is always biased upward counterclockwise around the rotation shaft 61b by the elastic biasing force of the spring 70, and the end on the tip side in the arm longitudinal direction A on the opposite side across the rotation shaft 61b is biased downward.

[0042] The second link 62 is connected to the end of the lock piece 52 on the base end side in the arm longitudinal direction A via a connecting shaft 62a. The connecting shaft 62a is disposed in a horizontal direction perpendicular to the arm longitudinal direction A and is rotatably provided on the slide portion 52a.

[0043] As shown in FIG. 5, when the rotation knob 80 is displaced to one side (positive side) by a first phase width (θ1°) from a dead point phase (0°) corresponding to the extension dead point of the link mechanism 60, the link mechanism 60 is in a first position where positional change is restricted and the lock piece 52 and the lock gear 51 are engaged. In this specification, the extension dead point refers to a state in which the connecting portions (connecting shafts 61a and 62a) of the link mechanism 60 are aligned in the same straight line along the arm longitudinal direction A and are maximally extended, as shown in FIG. 6, and the rotational phase of the rotation knob 80 at this time is referred to as the dead point phase (0°). When the clockwise direction in FIG. 5 is defined as the positive direction, the first phase is a phase in which the rotation knob 80 has rotated by +θ1° from the dead point phase (0°). The end of the first link 61 on the tip side in the arm longitudinal direction A abuts against the lower plate 10b of the first arm 10, restricting positional change and maintaining the position by the biasing force of the spring 70.

[0044] 7 and 10, when the rotary knob 80 is displaced from the dead center phase (0°) toward the other side (negative side) opposite the one side by a second phase width (θ2°) that is greater than the first phase width (θ1°), the link mechanism 60 is in the second posture, and the engagement between the lock piece 52 and the lock gear 51 is released. When the link mechanism 60 is in the second posture, the first link 61 and the second link 62 bend downward in a dogleg shape, and the lock piece 52 moves back, thereby releasing the engagement with the lock gear 51. The second phase is a phase in which the rotary knob 80 has rotated by −θ2° from the dead center phase (0°) when the clockwise direction in FIG. 5 is defined as the positive direction, and the end of the first link 61 on the tip side in the arm longitudinal direction A abuts against the upper plate 10a of the first arm 10, thereby restricting the change in posture.

[0045] The spring 70 is a spiral coil spring that generates an elastic force when contracted in the axial direction, and is inserted onto the connecting pin 71 and interposed between the plate-shaped end 61d of the first link 61 and the lower plate 10b of the first arm 10.

[0046] The rotation knob 80 is composed of a knob shank 80a and an operating unit 80b. The knob shank 80a is a round bar-shaped member and is disposed horizontally in a direction perpendicular to the arm longitudinal direction A. One end of the knob shank 80a is fixed to the second link 62 inside the first arm 10, and the other end protrudes laterally from the first arm 10. The operating unit 80b is a member that an operator grips with their hand to rotate the knob shank 80a. The operating unit 80b has a disk or columnar shape with a larger diameter than the knob shank 80a and is fitted to the other end of the knob shank 80a that protrudes laterally from the first arm 10. Gripping and rotating the operating unit 80b with their hand rotates the knob shank 80a, and the second link 62, to which the knob shank 80a is fixed so as not to rotate, rotates via the connecting shaft 62a.

[0047] <Procedure for changing the rotation angle of the second arm 20 and operation of each part> Next, the procedure for changing the rotation angle of the second arm 20 and the operation of each part of the swing arm 4 during this procedure will be described.

[0048] The link mechanism 60 normally maintains the lock mechanism 50 in a locked state by the biasing force of the spring 70. That is, as shown in Figures 5 and 8, the link mechanism 60 is in a first posture in which the spring 70 biases the plate-shaped end 61d of the first link 61 in a direction pushing it upward, the corner portion on the tip side of the second link 62 connected to the first link 61 abuts against the lower plate 10b, and the lock piece 52 is maintained in a position slightly retreated from the maximum forward position (maximum extension position of the link mechanism 60) and engaged with the lock gear 51. At this time, the rotation knob 80 is maintained in a state displaced by the first phase width (+θ1°) from the dead center phase (0°).

[0049] Next, in order to change the rotation angle of second arm 20 relative to first arm 10 to match the lift-up point of the vehicle, the worker grips operating portion 80b of rotation knob 80 with one hand and turns it counterclockwise in Fig. 5 against the biasing force of spring 70. Then, lock piece 52 advances via second link 62 and reaches the maximum advance position (maximum extension position of link mechanism 60) at the dead center phase (0°) as shown in Figs. 6 and 9. If the rotation knob 80 is then further turned counterclockwise, first link 61 and second link 62 bend downward in a dogleg shape as shown in Figs. 7 and 10, and lock piece 52 retreats via second link 62, disengaging from lock gear 51. At this time, the second link 62 assumes a second position in which the corner portion at the tip end abuts the upper plate 10a, and the counterclockwise rotation of the rotating knob 80 is restricted while displaced by the second phase width (-θ2°) from the dead center phase (0°).

[0050] 7 and 10, the operator rotates the second arm 20 horizontally with the other hand. For example, the operator rotates the second arm 20 horizontally from a position where the second arm 20 is at a relative angle of 0° with respect to the first arm 10 (see FIG. 2), through a position where the second arm 20 is at a relative angle of 45° (see FIG. 3), and finally to a position where the second arm 20 is at a relative angle of 90° (see FIG. 4). When the operator releases the grip of the rotary knob 80 with one hand while the second arm 20 is at the desired rotation angle with respect to the first arm 10, the biasing force of the spring 70 causes the link mechanism 60 to transition to the first position, and the rotary knob 80 is displaced clockwise by the first phase width (+θ1°) from the dead center phase (0°). This causes the link mechanism 60 to extend, moving the lock piece 52 forward and engaging with the lock gear 51, returning the lock mechanism 50 to the locked state. The corner portion of the tip side of the second link 62 abuts against the lower plate 10b, maintaining the position.

[0051] <Summary of the embodiment> As is clear from the above detailed description, the vehicle maintenance lift 1 according to this embodiment is a vehicle maintenance lift including a carriage 3 that can be raised and lowered, and a swing arm 4 that is pivotally attached to the carriage 3 so as to be horizontally rotatable and that has a receiving metal 30 at its tip as a vehicle receiving portion, and the swing arm 4 is configured to have a base arm 5, a first arm 10 that is provided so as to be slidable in the arm longitudinal direction A relative to the base arm 5, and a second arm 20 that is pivotally attached to the tip side of the first arm 10 so as to be horizontally rotatable, and the vehicle maintenance lift 1 has a lock gear 51 provided at the base end of the second arm 20, and a lock piece 52 that is provided on the first arm 10 so as to be able to engage and disengage with the lock gear 51, and The device comprises a locking mechanism (50) that locks the rotation of the arm (20) relative to the first arm (10); a link mechanism (60) consisting of a plurality of links connected to each other, one end of which is supported by the first arm (10) and the other end of which is connected to a locking piece (52), and which is capable of changing its position between a first position in which the locking piece (52) engages with the lock gear (51) and a second position in which the locking piece (52) is separated from the lock gear (51) and the engagement is released; a spring (70) as a biasing member provided between the first arm (10) and the link mechanism (60) that biases the link mechanism (60) in the direction of assuming the first position; and a rotating knob (80) as an operating member that acts on a predetermined portion of the link mechanism (60) to change the link mechanism (60) from the first position to the second position against the biasing force of the spring (70).

[0052] According to this configuration, the link mechanism 60 is normally held in the first position by the biasing force of the spring 70, and the lock piece 52 is engaged with the lock gear 51, so that the rotation of the second arm 20 is reliably locked, ensuring safety. Meanwhile, by using the action of the rotation knob 80 to change the link mechanism 60 from the first position to the second position against the biasing force of the spring 70, the lock piece 52 moves away from the lock gear 51 and is disengaged from the lock gear 51, so that the lock on the rotation of the second arm 20 can be easily released with a small force. Therefore, the operating force required to unlock the rotation of the second arm 20, which is pivotally mounted on the tip side of the first arm 10 in the swing arm 4 so as to be horizontally rotatable, can be reduced, thereby providing a vehicle maintenance lift 1 that can be easily unlocked.

[0053] The rotary knob 80 extends in the thrust direction S relative to the link mechanism 60 .

[0054] According to this configuration, the rotary knob 80 is provided to extend in the thrust direction S (a direction parallel to the axial direction of each connecting shaft 61 a, 62 a of the link mechanism 60) relative to the link mechanism 60, and therefore the link mechanism 60 can be changed from the first position to the second position by operating the rotary knob 80 in a direction different from the sliding direction of the first arm 10. In other words, if the rotary knob 80 were provided to extend in the radial direction relative to the link mechanism 60, the operating direction of the rotary knob 80 would be the same as the sliding direction of the first arm 10, which could lead to the first arm 10 being erroneously slid when unlocking the second arm 20; however, according to the above configuration, erroneous operation of sliding the first arm 10 can be avoided.

[0055] Further, the thrust direction S of the link mechanism 60 is a horizontal direction perpendicular to the arm longitudinal direction A.

[0056] According to this configuration, the thrust direction S of the link mechanism 60 is a horizontal direction (in other words, a left-right direction with respect to the swing arm 4) that is perpendicular to the arm longitudinal direction A, and therefore the rotary knob 80 is provided to extend in the left-right direction with respect to the swing arm 4. Therefore, the height size of the rotary knob 80 in the swing arm 4 that is inserted between the underside of the vehicle and the installation surface is suppressed, making it possible to avoid interference between the rotary knob 80 and the vehicle.

[0057] The rotary knob 80 is a rotary operating member that rotates the link mechanism 60 by a predetermined angle around an axis that extends in the thrust direction S at a predetermined position of the link mechanism 60 .

[0058] According to this configuration, link mechanism 60 can be changed from the first position to the second position by rotating rotation knob 80 by a predetermined angle around an axis that is provided at a predetermined portion of link mechanism 60 and extends in thrust direction S. In this configuration, the sliding direction of first arm 10 and the operating direction of rotation knob 80 are different, so that it is possible to prevent first arm 10 from sliding accidentally when unlocking second arm 20, thereby improving safety.

[0059] The rotary knob 80 is a rotary operating member that is gripped and rotated by hand.

[0060] With this configuration, link mechanism 60 can be easily changed from the first position to the second position by gripping rotation knob 80 with one's hand and rotating it a predetermined angle around its axis. Furthermore, accidental contact of the worker's hand or foot with rotation knob 80 will not release the lock on second arm 20, preventing mistaken release of the lock on rotation of second arm 20 and improving safety.

[0061] Furthermore, when the rotary knob 80 is displaced from the dead point phase (0°) corresponding to the extension dead point of the link mechanism 60 to one side (+ side) by a first phase width (θ1°), the link mechanism 60 is in a first posture where positional change is restricted and the lock piece 52 and the lock gear 51 are engaged, and when the rotary knob 80 is displaced from the dead point phase (0°) to the other side (- side) opposite the one side by a second phase width (θ2°) that is larger than the first phase width (θ1°), the link mechanism 60 is in a second posture where the engagement between the lock piece 52 and the lock gear 51 is released.

[0062] According to this configuration, when the rotary knob 80 is moved away from the dead center phase by the first phase width (θ1°) to one side (positive side), the link mechanism 60 is restricted from changing its position in the first position, and the lock piece 52 and the lock gear 51 are engaged, so that the rotation of the second arm 20 is securely locked and the locked state is maintained. On the other hand, when the rotary knob 80 is operated to move the rotary knob 80 away from the dead center phase (0°) to the other side (negative side) by the second phase width (θ2°), the engagement between the lock piece 52 and the lock gear 51 is released in the second position, so that the lock on the rotation of the second arm 20 can be easily and securely released by simply operating the rotary knob 80.

[0063] The rotary knob 80 also acts on the second link 62, which is a specific link connected to the lock piece 52, to change the connection angle with respect to the lock piece 52.

[0064] With this configuration, the rotatable knob 80 acts on the second link 62 to change the connection angle relative to the locking piece 52, thereby changing the link mechanism 60 from the first position to the second position with a small force. Furthermore, because the rotatable knob 80 acts on the second link 62 that is connected to the locking piece 52, the rotatable knob 80 can be positioned closer to the tip of the first arm 10, ensuring a large sliding range for the first arm 10 relative to the base arm 5.

[0065] <Modification> The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit and scope of the present invention. For example, in the above embodiment, the base arm 5 includes the base arm main body 5a and the slider 5b inserted into the inner periphery of the base arm main body 5a and slidable in the arm longitudinal direction. However, the present invention is not limited to this. For example, the base arm 5 may be configured with only the base arm main body 5a, and the first arm 10 may be provided slidable in the arm longitudinal direction A relative to the base arm main body 5a. Alternatively, in addition to the base arm main body 5a and the slider 5b, second, third, etc. sliders may be provided inserted into the inner periphery of the slider 5b and slidable in the arm longitudinal direction A.

[0066] Furthermore, in the above embodiment, an example was shown in which the rotary knob 80 that is gripped and rotated by hand is used as the rotary operation member, but a lever-shaped member may also be used as the rotary operation member.

[0067] Furthermore, in the above embodiment, an example was shown in which the present invention was applied to a floor-mounted column-type vehicle maintenance lift that has a column 2 erected on the floor surface and raises and lowers the carriage 3 along the column 2, but the present invention is not limited to this. For example, the present invention may be applied to an embedded column-type vehicle maintenance lift in which a column is buried in the floor, a carriage is provided at the top end, and the carriage is raised and lowered by a ram cylinder, a screw mechanism, or the like, or a vehicle maintenance lift in which the carriage is raised and lowered by a link mechanism such as an X-link type, a pantograph type, or a λ (lambda) link type. [Explanation of symbols]

[0068] 1. Vehicle maintenance lift 2 pillars 3 carriages 4 Swingarm 5 Base Arm 10 First Arm 20 Second Arm 30 Receptacle (vehicle support part) 50 Locking mechanism 51 Lock Gear 52 Lock piece 60 Link mechanism 61 First Link (Multiple Links) 62 Secondary Links (Multiple Links, Specific Links) 70 Spring (biasing member) 80 Rotating knob (operating member, rotating operating member) A Arm longitudinal direction S Thrust direction θ1 1st phase width θ2 2nd phase width

Claims

1. A vehicle maintenance lift comprising: a carriage that can be raised and lowered; and a swing arm that is pivotally attached to the carriage so as to be horizontally rotatable and has a vehicle receiving portion at its tip, the swing arm is configured to include a base arm, a first arm slidably provided in the arm longitudinal direction relative to the base arm, and a second arm pivotally attached to a tip end side of the first arm so as to be horizontally rotatable; The vehicle maintenance lift is a lock mechanism that includes a lock gear provided at a base end of the second arm and a lock piece provided on the first arm so as to be able to engage and disengage with the lock gear, and that locks the second arm against rotation with respect to the first arm; a link mechanism including a plurality of links connected to each other, one end of which is supported by the first arm and the other end of which is connected to the lock piece, and which is capable of changing its position between a first position in which the lock piece engages with the lock gear and a second position in which the lock piece is separated from the lock gear and the engagement is released; a biasing member provided between the first arm and the link mechanism and biasing the link mechanism in a direction to assume the first posture; an operating member that acts on a predetermined portion of the link mechanism to change the link mechanism from the first position to the second position against the biasing force of the biasing member; A vehicle maintenance lift equipped with:

2. 2. The vehicle maintenance lift according to claim 1, wherein the operating member extends in a thrust direction relative to the link mechanism.

3. 3. The vehicle maintenance lift according to claim 2, wherein the thrust direction of the link mechanism is a horizontal direction perpendicular to the longitudinal direction of the arm.

4. 4. The vehicle maintenance lift according to claim 2, wherein the operating member is a rotation operating member that rotates the link mechanism by a predetermined angle around an axis that extends in the thrust direction at a predetermined portion of the link mechanism.

5. 5. The vehicle maintenance lift according to claim 4, wherein the rotation operating member is a rotation knob that can be gripped and rotated by hand.

6. 4. The vehicle maintenance lift according to claim 1, wherein when the operating member is displaced from the dead point phase corresponding to the extension dead point of the link mechanism to one side by a first phase width, the link mechanism is in the first position where position change is restricted and the lock piece and the lock gear are engaged, and when the operating member is displaced from the dead point phase to the other side opposite to the one side by a second phase width greater than the first phase width, the link mechanism is in the second position where the engagement between the lock piece and the lock gear is released.

7. 7. The vehicle maintenance lift according to claim 6, wherein the operating member acts on a specific link connected to the lock piece to change a connection angle with respect to the lock piece.

Images