JPH0676299U - Safety equipment for vehicle lifts - Google Patents

Abstract

(57) [Summary] [Purpose] To provide a safety device for a vehicle lift, in which a safety device is stored only under the floor surface and reliability can be ensured even if maintenance and inspection work is almost unnecessary. [Structure] In a cylinder 2 of a single-acting hydraulic lift 1, a rotatable screw rod 4 which penetrates an upper portion of a lid 3 of the cylinder 2 in an airtight manner is housed in parallel with an elevating rod 5. The ball nut 6 screwed to the rod 4 and the lower part of the lifting rod 5 are connected by a connecting arm 7, and the screw rod 4
A ratchet wheel 8 is fixed to the protruding portion of the ratchet wheel, and a ratchet pawl 9 of the ratchet wheel 8 is provided on a fixed portion such as the upper surface of the lid 3.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a safety device for a vehicle lift, and more particularly to an improvement of a safety device for a single-acting vehicle lift that has a function of preventing the lift from falling in any of the up and down positions.

[0002]

[Prior art]

 Conventionally, as a safety device for a single-acting vehicle lift, a device shown in FIG. 6 has been proposed. In this conventional example, a rack 8a is hung from a loading table 12 attached to the upper end of a lifting rod 5 of a single-acting lift 1, and a pawl 9a that is detachably engaged with the rack 8a is fixed to a lower fixed portion of a floor surface F. The claw 9a is pivotally supported, and the claw 9a is normally urged in a direction to lock the claw 9a to the rack 8a, and the rack 8a of the claw 9a is resisted against the urging force of the spring 13 when the lift is lowered. It is connected to a detaching device 11 composed of a solenoid or the like for detaching the engagement with.

In the above-described conventional vehicle lift safety device, when the lifting rod 5 is lifted by hydraulic pressure (the hydraulic circuit portion is not shown), the rack 8a is also lifted along with it. The teeth of 8a open by pushing the pawl 9b against the urging force of the spring 13 and rise, but if the lift (to be exact, the lifting rod 5) lowers unintentionally due to oil leakage or the like, the rack 8a The claw 9a is engaged with one of the valleys of the 8a (the claw 9 is prevented from rotating by the stopper 17 or the like) to make it impossible to descend, and it is desired to lower the lift. In this case, the desorption device 11 is first operated to disengage and engage the claw 9a, and then the normal lowering operation is performed.

[0004]

[Problems to be solved by the device]

 However, in the above-described conventional vehicle lift safety device, the rack 8a moves in and out below the floor surface F as the lift moves up and down. Therefore, in this conventional example, the storage bit of the rack 8a must be provided on the floor surface F. Moreover, since the rack 8a has teeth, it is difficult to seal the rack 8a. There is a problem that it is difficult to prevent foreign matter (especially, muddy water when the vehicle is washed) from entering the bit that stores 8a.

If muddy water or the like enters into the bit that houses the rack 8a, it may cause corrosion and wear of the drive unit, and further, the drive unit may become rusted and the initial mechanical operation cannot be performed. The problem is that safety cannot be ensured unless maintenance work is performed.

Therefore, the present invention has been made to solve the above-mentioned problems, and a safety device is stored only under the floor surface F, so that reliability can be ensured even if maintenance work is almost unnecessary. It is intended to provide a safety device.

[0007]

[Means for Solving the Problems]

 In order to solve the above-mentioned problems, the structure of the present invention based on the above-mentioned utility model registration claim is based on the above-mentioned object. A rotatable screw rod 4 which extends in an airtight manner is housed in parallel with the elevating rod 5, and a ball nut 6 screwed to the screw rod 4 and a lower portion of the elevating rod 5 are connected by a connecting arm 7. Further, a technical means is adopted in which the ratchet wheel 8 is fixed to the protruding portion of the screw rod 4 and the ratchet pawl 9 of the ratchet wheel 8 is provided at a fixed portion such as the upper surface of the lid 3. is there.

[0008]

[Action]

 Next, the operation of the present invention will be described with reference to the accompanying drawings. First, in order to raise the lift, driving oil is pumped into the cylinder 2 as in the conventional case. This drive oil is supplied by operating the pump 21 shown in FIG. 5 as in the conventional case. When the drive oil is pumped into the cylinder 2, the elevating rod 5 rises by an amount corresponding to the pumped drive oil amount. Is also the same as the conventional operation.

When the elevating rod 5 rises, the connected ball nut 6 naturally rises accordingly. When the ball nut 6 rises, the screw rod 4 is rotatably supported, so that the screw rod 4 and the ratchet wheel 8 rotate. The rotation of the screw rod 4 is set so that the ratchet wheel 8 rotates normally when the lift rises and reverse when the lift descends, so that when the lift is raised, the ratchet wheel 8 does not exist at all. It acts so as not to affect the rise of.

Next, it is assumed that the lift is raised to a desired position and, in this state, the lift is lowered due to oil leakage or the like. Then, the elevating rod 5 or the ball nut 6 descends, so that the screw rod 4 is reversed. However, in this case, since the screw rod 4 prevents the ratchet wheel 8 and the ratchet pawl 9 from rotating in the reverse direction, the screw rod 4 cannot rotate in the reverse direction, so that the lift is prevented from falling. .

In addition, when lowering the lift, the engagement of the ratchet pawl 9 may be detached by a detaching device such as a solenoid as in the conventional case. After the engagement of the ratchet pawl 9 is detached, as shown in FIG. In this embodiment, the solenoid valve 22 is opened to return the drive oil in the cylinder 2 to the tank 23, thereby lowering the lifting rod 5.

In the present invention, the vertical movement of the lifting rod 5 is converted into the rotation of the ratchet wheel 8 to prevent the lift from falling, so that the force finally applied to the ratchet pawl 9 is attenuated. The reliability is improved and the entire safety device can be completely stored under the floor surface F. In other words, the lid can be fixed and sealed above the safety device.

[0013]

【Example】

 Next, an embodiment of the present invention will be described. In the figure, 1 is a single-acting hydraulic lift, and this single-acting lift 1 has a lifting rod 5 that penetrates the upper portion of a cylinder 2 in an airtight manner. As in the conventional case, the lifting rod 5 is moved up and down.

The driving oil can be put in and taken out of the cylinder 2 by a conventionally known hydraulic unit 20, and the hydraulic unit 20 of the present embodiment has a tank 23 and a cylinder 2 as shown in FIG. And a pump 21 in the middle of the connecting pipe 24, and a check valve 25 between the pump 21 and the cylinder 2 in the connecting pipe 24. is there. Then, a return flow path 26 returning to the tank 23 is branched from a portion of the connecting pipe 24 between the check valve 25 and the cylinder 2, and in the middle of the return flow path 26, the return flow path is provided only when the solenoid 22a is energized. A solenoid valve 22 is provided to bring the passage 26 into communication.

In this embodiment, a flange 2a is provided on the bottomed cylinder 2, a lid 3 is fixed on the flange 12, and a metal 31 penetrating the lid 3 is provided. The metal 31 is guided to move up and down, but the flange 2a and the lid 3 may be omitted and the metal 31 may be directly fitted and fixed in the upper opening of the cylinder 2.

A rotatable screw rod 4 is housed in the cylinder 2 in parallel with the elevating rod 5 so that an upper portion of the screw rod 4 extends through the lid 3 of the cylinder 2 in an airtight manner.

The screw rod 4 uses a ball bolt (ball screw) with which a ball nut 6 described later meshes. The lower end portion is a bearing 41, and the upper portion without screws is a metal 43 for keeping airtightness with a packing 42. Each is rotatably supported.

Further, although the screw rod 4 is rotatable, it is supported so that it cannot be lifted and lowered. In the illustrated example, the flange portions 43, 43 of the screw rod 4 cannot lift the screw rod 4.

When the lid 3 is omitted as described above, the upper portion of the screw rod 4 may be made to project from the flange portion 32 of the metal 31 of the elevating rod 5 or the like, as in the illustrated embodiment. In addition, if the metal 3 of the lifting rod 5 and the metal 43 of the screw rod 4 are separately prepared, the packing 33, 42 of both metals 3, 43 can be replaced easily by simply removing the respective metal 3, 43. Therefore, it is desirable.

A ball nut 6 screwed to the screw rod 4 and a lower portion of the elevating rod 5 are connected by a connecting arm 7. The connection between the ball nut 6 and the elevating rod 5 by the connecting arm 7 may be made immovable, but if a force other than the vertical up and down direction is applied to the screw rod 4, the screw rod 4 is bent, Since the conduction between the ball nut 6 and the screw rod 4 may not be carried out smoothly, in this embodiment, the force from the connecting arm 7 is always applied to the ball nut 6 in the vertical vertical direction.

That is, as shown most clearly in FIG. 3, the ball nut 6 has an outer cylinder 61 that is loosely fitted therein and is pivotally supported by a horizontal shaft 62, and is connected to the upper and lower ends of the outer cylinder 61. The tip of the connecting arm 7 is inserted between the flange portions 63, 63.

Further, at the tip of the connecting arm 7, there are provided load receiving portions 72, 72 having upper and lower spherical seat portions 71. The load receiving portions 72, 72 are arranged so as to be positioned at a position orthogonal to the shaft 62. There is.

Therefore, the outer cylinder 61 has a function of a universal joint, and when the connecting arm 7 moves up and down, it moves in a direction other than the vertical direction (when an unbalanced load is applied to the lift, the lifting rod 5 is slightly inclined. However, the ball nut 6 always receives a force only in the vertical direction. In addition to the tilting force, the lifting rod 5 may be applied with a rotating force about the center axis as a rotating axis. In this case, since the load receiving portions 72, 72 may be displaced from the flange portions 63, 63, if necessary, a stopper (a screw in the figure) that limits the displacement of the load receiving portions 72, 72 in the horizontal plane direction within a certain range. For the purpose of preventing the rod 4 from bending, rails 73, 73 are fixed vertically on both sides of the load receiving portions 72, 72.).

A ratchet wheel 8 is fixed to the protruding portion of the screw rod 4, and a ratchet pawl 9 of the ratchet wheel 8 is provided at a fixed portion such as the upper surface of the lid 3.

The ratchet wheel 8 and the ratchet pawl 9 are conventionally well known, and are designed to allow forward rotation but inhibit reverse rotation. The ratchet pawl 9 is provided with a spring 13 that constantly biases the ratchet pawl 9 in a direction in which the ratchet pawl 9 is locked to the ratchet wheel 8.

The ratchet pawl 9 is connected with a detaching device 11 such as a solenoid capable of detaching the engagement with the ratchet wheel 8 when necessary, and when the lift is lowered, the ratchet pawl 9 is engaged with the ratchet wheel 8. The drive oil in the cylinder 2 is returned to the tank 23 after the connection and removal. Further, in this embodiment, as shown in FIG. 2, a detachment confirmation sensor 14 for the ratchet pawl 9 is provided, and the solenoid valve 22 is operable after the detachment confirmation sensor 14 confirms the attachment / detachment of the ratchet pawl 9. It has been done.

In the above description, the reason why the detachment confirmation sensor 14 is attached is that if the elevating rod 5 is lowered before detaching the ratchet pawl 9, the ratchet pawl 9 and the ratchet wheel 8 are firmly meshed with each other. This is because the ratchet claw 9 cannot be attached or detached by the detaching device 11 thereafter. Even when the safety device of the present invention functions, the ratchet claw 9 and the ratchet wheel 8 are in a tight meshing state, but in this case, the lifting rod 5 is once raised and then lowered for safety confirmation. It is advisable to do so.

Incidentally, reference numeral 30 in the figure shows an outer box for housing the lift 1. The outer box 1 is embedded in the floor surface F 1 as in the conventional case. The outer box 1 is preferably configured so that the upper side of the ratchet wheel 8 and the like is covered with a cover plate 34 to prevent foreign matter from entering. Further, 52 is a scraper and 51 is a wear ring. Further, although omitted in the drawing, a loading platform 12 (see "Fig. 6") is attached to the upper end of the lifting rod 5.

[0029]

[Effect of device]

 As described above, according to the present invention, the vertical movement of the lifting rod 5 is converted into the rotation of the ratchet wheel 8 to prevent the lift from falling. Therefore, a safety device for a vehicle lift that can easily and surely perform sealing. Can be provided.

In the present invention, since the screw rod 4 and the ball nut 6 screwed to the screw rod 4 are housed in the cylinder 2, both are soaked in the driving oil and maintenance and inspection are almost unnecessary. In addition, since the nine ratchet wheels are located on the upper surface of the lift 1, it is possible to provide a safety device for a vehicle lift that is easy to maintain and inspect.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a lift having a safety device for a vehicle lift according to the present invention.

FIG. 2 is a plan view of the lift with a cover plate removed.

FIG. 3 is an enlarged vertical sectional view of a lower portion of the lift.

FIG. 4 is a cross-sectional view taken along the line AA of “FIG. 3”.

FIG. 5 is a hydraulic circuit diagram.

FIG. 6 is a schematic front view of a conventional example.

[Explanation of symbols]

 1 Lift 2 Cylinder 3 Lid 4 Screw Rod 5 Lifting Rod 6 Ball Nut 7 Connecting Arm 8 Ratchet Wheel 9 Ratchet Claw

Claims (1)

[Scope of utility model registration request] 1. A single-acting hydraulic lift (1) includes a rotatable screw rod (4) in a cylinder (2) of which an upper portion thereof extends through a lid (3) of the cylinder (2) in an airtight manner. , A ball nut (6) which is housed in parallel with the lifting rod (5) and is screwed onto the screw rod (4), and the lower portion of the lifting rod (5) are connected by a connecting arm (7), and the screw A ratchet wheel (8) is fixed to the protruding part of the rod (4), and a ratchet wheel (8) of the ratchet wheel (8) is provided at a fixed portion such as the upper surface of the lid (3). All devices.