JPH0213431Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a lifter that can be quickly lifted up by simple operation. Among these types of devices that allow relatively lightweight objects such as bicycles and minibikes to be raised and lowered, there have been the following types of devices that do not require a power source. That is, FIG. 1 shows the conventional device, in which a trolley 2 equipped with rollers 1, 1 and a pedestal 3 are connected by each pair of arms 4, 5 arranged in a pantograph shape, and the shaft of one arm 4, 4 is The tip of a piston rod 8 of a cylinder 7 is connected to the branch 6, and the piston rod 8 can be extended by stepping on a pedal 9, while opening and closing of the pressurized air in the cylinder 7 can be controlled by operating a handle 10. , the piston rod 8 was made smaller. In the figure, 11
is a step connected at one end to the pedestal 3. However, in this conventional device, in order to obtain the desired lifting height of the pedestal 3, it is usually necessary to press the pedal 9 10 to 30 times. The handle 10 must be operated every time the cylinder 7 is raised or lowered, which is cumbersome. Furthermore, the use of the cylinder 7 increases the number of incidental parts including the handle 10, making manufacturing complicated and complicated, which increases manufacturing costs. On the other hand, if the pressure oil in the cylinder 7 were to leak, there was a risk that an unexpected situation would occur, which made the cylinder 7 uncomfortable. Further, in the above device, since the cylinder 7 was disposed between the lower ends of the arms 4 and 5, the cylinder 7
There is a problem in that the vertical movement of the pedestal 3 is limited by the cylinder 7, and if the cylinder 7 is disposed outside the truck 2, for example, the entire device becomes large and heavy. The present invention improves these conventional drawbacks and uses a gear mechanism with a worm and worm wheel instead of a cylinder, making it possible to quickly lift up with a small drive operation, reducing the burden of labor. While ensuring reliable and safe operation, we have also reduced the number of parts to facilitate manufacturing and reduce manufacturing costs.In addition, we have made it possible to achieve smaller size, lighter weight, higher lift, and stronger strength.
The purpose is to provide a type of lifter that does not require a power source. For this reason, the lifter of the present invention is a lifter in which the machine platform and the platform are connected by a pair of left and right arms forming a pantograph link mechanism, and the platform can be raised and lowered. A gear type reduction mechanism consisting of a worm wheel and a pair of gears is provided, and the worm is placed directly below the worm wheel, and the tip of the worm shaft to which the worm is fixed is rotatably supported on the machine base. , and a plurality of pedals are disposed at the tip of the shaft, an intermediate shaft to which a worm wheel is fixed is disposed approximately in the middle of the machine base, and a gear having a larger diameter than the worm wheel is fixed to the intermediate shaft. , an arm shaft to which a small-diameter gear that meshes with the gear is fixed is rotatably supported on the end side of the machine base;
The present invention is characterized in that the lower end of each of the left and right arms is fixed to both ends of the arm shaft, so that the arm can be raised and lowered integrally with the arm shaft. Hereinafter, one embodiment of the present invention will be described with reference to the drawings. In FIGS. 2 to 7, reference numeral 12 indicates a pair of frames 13, 13 having a U-shaped cross section, and a pair of frames 14, 14 having an irregular cross section. The machine frame is constructed of a frame, and wheels 15 are rotatably provided at its four corners. Reference numeral 16 denotes a pedestal frame formed to have approximately the same shape as the machine pedestal 12. A pair of arms 17 and 18 are arranged in a pantograph shape between the back surface of the pedestal frame 16 and the machine pedestal 12. One of the arms 17, 17 is disposed adjacent to the outside of the other arm 18, one end of which is rotatably pivoted to the end position of the back surface of the pedestal 16, and the other end is provided with a roller 19. This roller 1 is rotatably supported on a shaft.
9 and 19 are fitted into the frames 13 and 13 so as to be movable. Further, rollers 20, 20 are rotatably supported at one end of the other arms 18, 18, and these rollers 20, 20 are mounted in guide rails 21, 21 fixedly spaced apart from each other on the back surface of the pedestal 16. The other end is fixed to the shaft end of the arm shaft 22. The arm shaft 22 is rotatably supported at the end of the machine base 12 via bearings 23, 23 provided at the inner ends of the frames 13, 13, and the arms 17, 18 are rotated depending on the direction of rotation. The stand 12 can be raised and lowered. 24 is a connecting rod that connects the arms 17 and 18 at approximately the center, and 25 is the frame 1.
Support frame installed between 3 and 13, 26, 26
is a reinforcing frame whose both ends are fixed between the frame 14 and the support frame 25, and a gear-type speed reduction mechanism is disposed thereon. The speed reduction mechanism supports the gearbox 27 at an intermediate position, and
Reference numeral 8 denotes a support plate fixed to the lower end of the frame 13, and a bearing 29 is provided on the plate.
An intermediate shaft 30 is rotatably supported between the gear box 9 and the gear box 27. 31 is a gear fixed to the arm shaft 22;
A gear 32 is fixed to the intermediate shaft 30 and meshes with the gear 31, and its pitch diameter is equal to that of the gear 3.
It is desirable that the diameter of the pitch circle is approximately twice or more than the diameter of the pitch circle. 33 is a worm wheel fixed to the intermediate shaft 30, 34 is a worm shaft rotatably supported between the frame 14 and the gearbox 27, and the worm wheel 3 is attached to one end of the worm shaft.
A worm 35 that meshes with the worm wheel 3 is fixed at a position directly below the worm wheel 33, and both the worm wheel 33 and the worm 35 are housed in the gear box 27. 36, 36 are thrust bearings arranged at both ends of the worm 35, and the worm wheel 33
The thrust load acting on the worm 35 through the worm shaft 35 and the displacement in the worm shaft 34 direction can be absorbed. Numeral 37 is a bushing fixed to the tip of the wormshaft 34 pulled out from the frame 14, and four pedals 38 as operating members are protruded from the circumferential surface of the bushing. In addition, reference numeral 39 in the figure represents a wheel mounting bracket fixed to the frame 14. In the lifter configured in this manner, the gear type reduction mechanism is disposed inside the machine base 12 , so the device can be made smaller compared to a lifter in which the mechanism is disposed outside. Since the arm shaft 22 constituting the machine base 12 is disposed at the end of the machine base 12 , the arm shaft 22 required for accommodating the arms 18, The length of the machine base 12 can be shortened, and the device can be made smaller accordingly. Moreover, a small-diameter gear 31 is fixed to the arm shaft 22 to prevent it from protruding from the machine base 12 , while an intermediate shaft 30 with a large-diameter gear 32 fixed to the machine base 12 is installed at a substantially intermediate position of the machine base 12. Because it is arranged,
The above-mentioned miniaturization is promoted. In addition, since the worm shaft 34 with the worm 35 fixed thereon, which engages with the worm wheel 33 at a position directly below it, is pivotally supported on the machine base 12 , the height of the machine base 12 can be made small, thereby reducing the size of the device. At the same time, the pedal 38 fixed to the tip of the shaft 34 is also made more compact. In such a lifter, the arms 17 and 18 are tilted horizontally and folded, and the pedestal 16 and the machine 12 are folded .
are almost polymerized and compacted. Therefore, in this state, the lifter can be easily carried and stored. Next, when lifting a load using a lifter from such a situation, place the load on the pedestal 16 in advance and hold it in place before lifting it up, then place your foot on the pedal 38 and lift it up. to rotate the pedal 38 in the same direction. When the pedal 38 rotates, the torque is applied to the worm 35 via the worm shaft 34 and transmitted to the worm wheel 33 that meshes with the worm 35. Therefore, the intermediate shaft 30 to which the worm wheel 33 is fixed rotates, the gear 32 fixed coaxially rotates, and the torque is transmitted to the arm shaft 22 via the gear 31 that meshes with the gear 32. As a result, the arms 18, 18, which have one end fixed to the arm shaft 22, stand up and rotate around the arm shaft 22, and connect the arms 1 through the connecting rod 24.
The other arms 17 and 17, which are pivotally connected to the arms 8 and 18, also stand up and rotate in conjunction with this.
The pedestal 16 supported by 7 and 18 rises, and the load is lifted up. In this case, warm 35
The number of threads of the worm wheel 33 is Z ₁ , the number of teeth of the worm wheel 33 is Z ₂ ,
If the number of teeth of gears 32 and 31 is Z ₃ and Z ₄ respectively, gear 3 when worm 35 is rotated by N ₁
The rotational speed N ₄ of the motor 1 is N ₄ =N ₁ ×Z ₁ ·Z ₃ /Z ₂ ·Z ₄ . Therefore, if the speed ratio between the worm 35 and the worm wheel 33 is set to 1/10, then N ₄ =N ₁・
Z ₃ /10Z ₄ , and if Z ₃ =2Z ₄ , then the number of revolutions of the gear 31 when the worm 35 is rotated once becomes Z ₄ =1/5. Therefore, the arm shaft 22 to which the gear 31 is fixed also rotates 1/5 turn (approximately 72 degrees), and the arms 17,
18 will be displaced by the same angle, but the arms 17 and 18 will be displaced by the same angle even at the maximum lifting height of the pedestal 16.
Because the standing angle is usually less than 70°,
The above settings are also sufficient for practical use.
In this case as well, if the number of threads or teeth of each gear is selected to increase the speed ratio, the wormshaft 34 can be rotated half a turn, that is, the two pedals 38 can be depressed continuously. Since it is possible to obtain a long lift head, compared to conventional devices of this type, the labor required for lift-up can be significantly reduced, and the lift-up can be done more quickly. In addition, in such a lift-up, the arms 18, 18 are connected to the arm shaft 2 as described above.
Since it stands up and rotates together with the arms 17 and 18, lift-up is performed reliably, and since a cylinder unlike the conventional one is not provided between the arms 17 and 18, the lift displacement of the pedestal 16 is limited by the cylinder. high maximum head can be set. In this way, when the pedestal 16 is lifted up and the arms 17 and 18 stand up, there is a concern that the weight of the load will act on them and cause buckling.
Since the lower end portions of the arms 8 and 18 are fixed to both ends of the arm shaft 22, the terminal coefficient becomes larger and the buckling strength is enhanced compared to those where the upper and lower ends are rotating ends. Furthermore, even if you take your foot off the pedal 38 during or after the lift-up operation, the frictional force acting on the tooth surface of the worm wheel 33 is extremely large, making it difficult to rotate the worm 35 and ensuring that the pedestal 16 is lowered. It is possible to prevent this from happening and ensure its safety, which eliminates the trouble of having to operate the valve each time as in the past, and also eliminates the need for dedicated parts, reducing the number of parts. This means that it is possible to achieve this goal. In this case, the worm 35 receives a thrust load from the worm wheel 33, but this load is applied to the thrust bearing 3.
6, 36 and has no effect on others. On the other hand, when lowering the frame 16, the pedal 38
is rotated in the opposite direction to rotate the worm shaft 34 in the opposite direction, rotate the worm 35, worm wheel 33, gears 32, 31 in the opposite direction, and rotate the arm shaft 22 in the opposite direction. Then, the arms 18, 18 rotate in the same direction, the other arms 17, 17 also follow this, are tilted, and the pedestal 16 is lowered. In this case as well, the pedal 38 only needs to be depressed two or three times, which can speed up the process. brakes the rotation of
In addition, since the accelerated rotation is suppressed, the pedestal 16 does not naturally or rapidly descend, and its safety can be ensured. 8 and 9 show an example of application of the present invention,
The same reference numerals are used for parts corresponding to the configurations of the previous embodiments. In this application example, gears 31 and 32
In addition, a gear box 27 is disposed approximately in the longitudinal center of the machine base 12, and the worm wheel 3 accommodated in the gear box 27 is omitted.
A pinion 40 is fixed coaxially with the pinion 3, and this pinion 40 is disposed in one frame 13' whose diameter has been increased, and long racks 41 and 42 that can mesh with the pinion 40 are installed in the frame 13'. and these racks 41 and 42 are housed in the frame 1.
3', each rack 41,
An arm 17 is connected to the outer end of the arm 42 via a pin 43.
18 is rotatably pivotally connected to the pinion 4.
A rotational displacement of 0 is transmitted to the racks 41 and 42, a linear displacement of the racks 41 and 42 is transmitted to the arms 17 and 18, and their base ends are moved toward and away from each other.
The feature is that the lifting and lowering operation of No. 6 is made faster. In the figure, 19' is a roller rotatably attached to the base end of arm 18 on the opposite side.
3 so that it can run. Therefore,
In this application example, since the raising and lowering displacement of the arms 17 and 18 is doubled, the number of rotations of the worm shaft 34 is halved compared to the above-described embodiment, and the labor burden is also halved. As described above, the lifter of the present invention uses a gear type reduction mechanism including a worm and a worm wheel instead of a conventional cylinder as a driving means for the arm supporting the pedestal. This has the effect of preventing situations from occurring and ensuring safety. In addition, by appropriately selecting the speed ratio of the gear type reduction mechanism, the pedestal can be raised and lowered with a slight rotation of the operating member, which reduces the labor required for lifting up compared to conventional devices of this type. This has the effect of significantly reducing the burden, increasing the speed of lift-up, and increasing the convenience of use. Moreover, since the present invention uses a worm and a worm wheel in the gear type reduction mechanism, a significantly large frictional force is obtained on the tooth surface of the worm wheel even during or after lift-up, and this suppresses the rotation of the worm. This eliminates the complication of having to operate a handle each time the frame is raised and lowered, as in the past, and also eliminates the need for special parts, which reduces the number of parts and simplifies the structure. It has the advantage of being easy to manufacture, and since it uses a pedal that can be rotated as an operating member, it can be operated while standing, making it a practical product that can further improve work efficiency. There is an effect. Furthermore, in the present invention, since the gear type reduction mechanism is disposed inside the machine base, the device can be made smaller compared to one in which it is disposed outside the machine base. The armshaft that
Since the shaft is disposed at the end of the machine base, the apparatus can be made more compact than when the shaft is disposed in the middle of the machine base. Moreover, a small-diameter gear is fixed to the armshaft to prevent it from protruding from the machine base, while an intermediate shaft with a large-diameter gear fixed to it is placed approximately in the middle of the machine base. , the above-mentioned miniaturization can be promoted. In addition, since the worm shaft with the worm fixed thereon, which engages with the worm wheel at a position directly below, is pivoted on the machine base, the height of the machine base can be reduced, which facilitates miniaturization of the equipment.
It is also possible to make the pedal fixed to the tip of the shaft more compact. When the lifter of the present invention is lifted up, the lower end of each arm stands up and rotates together with the arm shaft, so the lift up can be carried out reliably, and a cylinder like the conventional one is arranged between the arms. Therefore, the lift displacement of the pedestal is not limited by the cylinder.
A high maximum lift can be set. Moreover,
Since the lower ends of the arms are fixed to both ends of the arm shaft, the buckling strength of the upper and lower ends is increased compared to those at the rotating ends, and this has the effect of increasing the strength of this type of lifter.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing a conventional example, Fig. 2 is a perspective view showing an embodiment of the present invention, and Fig. 3 is a plan view showing the main part of the present invention, with a part cut away to show a sectional view. , FIG. 4 is an enlarged sectional view taken along the line A-A' in FIG. 2, FIG. 5 is an enlarged sectional view taken along the line B-B' in FIG. 7 is an enlarged sectional view taken along line D-D' in FIG. FIG. 9 is a side view showing an enlarged main part of FIG. 8, and a partially cutaway sectional view. 12 ... Machine base, 16... Frame, 17, 18...
Arm, 30... intermediate shaft, 33... worm wheel, 34... worm shaft, 35... worm, 38... operating member.

Claims (1)

[Scope of utility model registration request] In a lifter in which a machine base and a pedestal are connected by a pair of left and right arms constituting a pantograph link mechanism, and the pedestal can be raised and lowered, a gear consisting of a worm, a worm wheel, and a pair of gears is mounted on one half of the inside of the machine base. A type reduction mechanism is provided, and the worm is placed directly below the worm wheel, and the tip of the worm shaft to which the worm is fixed is rotatably supported on the machine base, and a plurality of While the pedal is disposed, an intermediate shaft to which a worm wheel is fixed is disposed approximately in the middle of the machine base, a gear having a larger diameter than the worm wheel is fixed to the intermediate shaft, and a gear having a small diameter meshes with the gear. An armshaft to which is fixed is rotatably supported on the end side of the machine base, and the lower end of each arm disposed on the left and right is fixed to both ends of the armshaft,
A lifter characterized in that the arm can be raised and lowered integrally with an arm shaft.