JPH04237604A - Wheel device - Google Patents

Abstract

PURPOSE:To constrain a wheel frame or release the constraint positively without being influenced by load by forming a wheel device for a dolly or the like in such a way that the operating part of a turning drive part is operated by the reverse rotation of a wheel so as to oscillate an oscillating frame and to perform engagement/ disengagement between an engaging part provided at a travel body base part and an engaging part provided inside the wheel frame. CONSTITUTION:During the travel of a travel body 2 in the direction of an arrow mark (a), an axle 8 is positioned more on the travel direction rear side than a pivot 4. An oscillating frame 14 is thereby energized upward, so that the first engaging part 10 of the base part 3 of the travel body 2 is engaged with the second engaging part 17 of a wheel frame 5 to constrain the wheel frame 5 and thereby to impede its turning around the pivot 4 as a fulcrum. In the case of reverse travel in the direction of an arrow mark a', friction frame mechanism 28 is rotated around a shaft 32 as a fulcrum by frictional resistance between the friction frame mechanism 28 and the side face of a wheel 9. The shaft 32 is thereby oscillated upward circularly around a shaft 18. At the same time, the oscillating frame 14 is oscillated upward by the cooperation between the friction operation aiding mechanism 34 and the wheel 9, so that the second engaging part 17 is lowered and released from its engagement with the engaging part 10 to obtain the unconstrained state.

Description

[Detailed description of the invention]

0001

[Industrial Field of Application] The present invention is applicable to, for example, large travel bags,
This invention relates to a wheel device installed at the bottom of a general cargo transport vehicle, a medical or various mechanical equipment transport vehicle or wagon, a hospital patient serving vehicle, etc.

0002

2. Description of the Related Art As is well known, there is a wheel device proposed by the present inventor and described in Japanese Patent Publication No. 11481/1981 as a wheel device installed at the lower part of a traveling body such as a variety of transport vehicles and wagons. The conventional wheel device described in the above-mentioned publication has an outer frame rotatably provided at the lower part of the mounting base, and further includes a swingable middle frame inside the outer frame, and brake pieces facing the outer peripheral surface of the wheel. When the wheels are rotating in the normal direction, the middle frame is not rocked, but when the wheels are in reverse rotation, the middle frame is rocked by the brake piece, and the restraining pin provided on the mounting base and the restraining means provided on the middle frame are engaged and disengaged. This configuration makes it possible.

0003

[Problems to be Solved by the Invention] However, in the conventional wheel device described above, the brake tabs face the outer circumferential surface of the wheel, so when the wheel is reversed, the brake claws bite into the outer circumferential surface of the wheel, causing the wheel to become damaged. However, if the outer frame still moves forward due to the running force of the traveling body, the middle frame swings to the extent that the wheel axle comes into contact with the end of the long hole in the outer frame, so the traveling body must run diagonally. Otherwise, the outer frame may not rotate. Further, if the outer peripheral surface of the wheel is worn down due to long-term use, or if there is deposits on the outer periphery of the wheel, the brake piece may not work and the outer frame may not turn. In addition, since the wheels are installed on the swinging middle frame, there are concerns about its strength.Especially when loading heavy objects on the running body or running transversely on an inclined surface, the middle frame alone will not be able to hold the load on the running body. may not be able to support the weight. Furthermore, since the inner frame is located inside the outer frame, it is not possible to modify and use a conventional wheel device, and a completely new wheel device must be created. therefore,
There is a need for a wheel device that has a structure that is not affected by any load, has a simple structure, can be easily used in conventional wheel devices, and has good running performance.

0004

[Means for Solving the Problems] The present invention has been proposed based on the above-mentioned needs, and includes a wheel frame that is provided at the base of the lower end of a traveling body so as to be able to swing freely laterally around a pivot shaft. A center perpendicular line and a center perpendicular line of a lateral wheel axle supporting a wheel provided on the wheel frame are spaced at a constant distance, a first engaging part is provided at the base part, and the base part is provided with a first engaging part; Inside the wheel frame, there is a swing frame having a second engagement part that engages and disengages from the first engagement part, a fixed frame located inside the swing frame and held by the wheel frame, and When facing the side of the wheel, when the vehicle is traveling in the forward direction, the wheel is rotating in the forward direction, so it does not operate, but when the vehicle is traveling in the opposite direction and the wheel is reversed, it operates. A swing drive unit is provided, and an operating unit of the swing drive unit swings the swing frame to convert engagement and disengagement between the first engagement part and the second engagement part. The present invention provides a wheel device that does the following:

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be explained below based on embodiments shown in the drawings. The wheel device 1 of the present invention is provided on a base 3 provided at the lower end of a traveling body 2. The traveling body 2 is a large travel bag, a wagon frame, a catering vehicle, a traveling frame, etc., and the base 3
In the first embodiment of the present invention, it is a flat plate attached to the lower surface of the traveling body 2. A pivot shaft 4 is provided on the lower surface of the base 3.
A wheel frame 5 is provided which can be rotated horizontally. The wheel frame 5 has an upper surface portion 6 supported by the pivot shaft 4, and a pair of left and right leg pieces 7, 7 extending downwardly at the left and right side edges of the upper surface portion 6. A wheel 9 is rotatably supported on a wheel shaft 8 installed below between the leg pieces 7, 7. Therefore, the center perpendicular X of the turning shaft 4 and the center perpendicular Y of the wheel axle 8 are separated by a certain distance because the leg piece 7 extends in an inclined shape.

[0006]The base portion 3 has a first engaging portion 10.
form. In the embodiment shown in the drawings, the first engaging portion 10 has a configuration in which a downward claw portion 12 is provided protruding from the front edge of a mounting frame 11 provided on the lower surface of one side edge of the base portion 3.

[0007] Further, a turning drive section 13 is provided inside and above the wheel frame 5. The swing drive unit 13 is configured to rotate the swing frame 1
4, a fixed frame 15 located inside the swing frame 14,
It has an actuating part 16 facing the fixed frame 15. The swing frame 14 has a shallow frame shape with an open bottom surface and has a second upward engaging portion 17 on the upper edge of one end, and has the pair of left and right leg pieces 7.
A first shaft 18 and a second shaft 1 are installed in the upper and rearward directions.
It is supported by 9. Specifically, the swing frame 14 is rotatably supported by the first shaft 18, and the second shaft 19 is inserted into arc-shaped regulation grooves 20 provided on the left and right sides of the swing frame 14. However, the arc-shaped regulating groove 20 has a short arc shape centered on the first shaft 18. Therefore, the swing frame 14 can rotate within the range of the length of the arcuate regulation groove 20 with the first shaft 18 as a fulcrum, but one end of the swing frame 14 can swing around the first shaft 18. Spring material 2 that presses the lower surface of the tip of the frame 14
1, the second engaging portion 17 is normally biased so that it rises and the second shaft 19 is located at the upper end of the arcuate regulating groove 20. The second engaging portion 17 is configured by forming a fitting groove 23 in the center of a vertical plate 22 that stands upright from the upper edge of the front end of the swing frame 14, and the left and right vertical plates extending from the fitting groove 23. The upper edge 24 of 22 slopes gently downward in an arc shape.

The fixed frame 15 is located inside the swing frame 14, and includes left and right fixed pieces 25, 25 and front and rear connecting pieces 26, 26.
It has a frame shape with an open top and bottom. And each fixed piece 2
A part of the upper edge of 5 constitutes a sliding edge 27 that is recessed in an arc shape. The fixed frame 15 has the first
Since the shaft 18 and the second shaft 19 are inserted and fixed, the wheel frame 5 can pivot as the wheel frame 5 rotates, but cannot swing together with the swing frame 14. Note that the other end of the spring member 21 that biases the swing frame 14 described above is fixed to a part of the fixed frame 15.

The operating section 16 includes a friction frame mechanism 28 located inside the swing frame 14 and a sliding frame mechanism 29 located inside the swing frame 14 and above the friction frame mechanism 28.
and has. The friction frame mechanism 28 is a downward U-shaped gate-shaped frame member in which leg-shaped friction pieces 31 , 31 extend downward on the left and right sides of the upper surface piece 30 . It is swingably provided on a third shaft 32 installed above, and friction pieces 31, 31 are provided on the left and right sides above the wheel 9.
is coming. A small piece-shaped friction part 33 is provided in a protruding manner on the inner edge of the tip of one of the friction pieces 31, and the friction part 33
is forcibly in contact with one side of the wheel 9. Further, a friction operation auxiliary mechanism 34 that rides on the outer surface of the substantially upper end of the wheel 9 is connected to the friction frame mechanism 28 . The friction actuation auxiliary mechanism 34
This is a structure in which arm rods 36, 36 extend from both ends of a freely rotatable roller 35, and the tips of both arm rods 36 are rotatably fixed to each friction piece 31 of the friction frame mechanism 28.

The sliding frame mechanism 29 described above is a friction frame mechanism 28.
It has a downward U-shaped gate frame shape with leg-shaped sliding pieces 38, 38 extending from the left and right ends of the upper surface part 37, in the same way as above.
It is rotatably supported by the third shaft 32 that swings together with the swing frame 14 . Then, the sliding frame mechanism 29
Since the width of the upper surface portion 37 is longer than the width of the upper surface piece 30 of the friction frame mechanism 28, the friction frame mechanism 28 is located inside the sliding frame mechanism 29. Further, the friction frame mechanism 28 and the sliding frame mechanism 29 can be operated at the same time by, for example, providing a low rising portion 30' protrudingly on the upper edge of the front part of the upper surface piece 30 and engaging with one side edge of the upper surface portion 37. It rotates. The width of the sliding frame mechanism 29 is approximately the same as the width of the fixed frame 15, and the arcuate sliding portions 39 at the lower edges of the left and right sliding piece portions 38 are connected to the fixed frame 15.
It is brought into contact with the sliding edge 27 of.

[0011] Therefore, a wheel frame 5 is rotatably provided on a base 3 provided on the lower surface of the traveling body 2 by a pivot shaft 4.
A swing drive unit 13 is placed above the wheel 9 provided inside the wheel frame 5.
is located. When the traveling body 2 is traveling in the direction of arrow a in FIG. Since the first engaging portion 10 and the second engaging portion 17 are engaged, the wheel frame 5 cannot pivot around the pivot shaft 4.
The wheel device 1 travels in a turning restrained state as shown in FIG. In the rotation restrained state of the wheel device 1 described above, the wheels 9
As the friction frame mechanism 28 rotates, the friction frame mechanism 28 slides, and no friction is applied. Further, since the rollers 35 of the friction operation assisting mechanism 34 are simply rotating idly, they do not provide any resistance to the rotation of the wheels 9.

However, when the traveling body 2 travels in the opposite direction as shown by the arrow a' in FIG. rotates around the third shaft 32, and due to the rotation of the friction frame mechanism 28, the third shaft 32 rotates around the first shaft 1.
It swings upward in an arc with 8 as the center. Since the friction operation auxiliary mechanism 34 rides on the outer peripheral surface of the wheel 9, it moves in the rotational direction of the wheel 9 and pulls the friction frame mechanism 28 at the same time as the wheel 9 rotates in the opposite direction.
8 automatically assists the start of the swinging of the swinging frame 14, and the sliding frame mechanism 29 is also forcibly rotated, so that the sliding piece portion 38
The arcuate sliding portion 39 is the sliding edge 2 of the fixed piece 25 of the fixed frame 15.
Slide 7. In addition, since the sliding edge 27 is formed so that the third shaft 32 can be raised in an arc shape to a predetermined position, the swing frame 14 can be moved up to the first position within the range of the arc-shaped regulation groove 20.
The second engaging part 17 descends and disengages from the first engaging part 10, and the wheel frame 5 enters an unrestricted state in which it can freely turn.

Immediately after the first engagement part 10 and the second engagement part 17 are disengaged, the center perpendicular Y of the wheel axle 8 moves forward in the traveling direction of arrow a' than the center perpendicular X of the turning shaft 4. Since the wheel frame 5 is located on the side, the ground resistance of the wheel 9 causes the wheel frame 5 to inevitably turn around the pivot axis 4, and when the wheel frame 5 rotates sufficiently, the center perpendicular line X of the pivot axis 4 will align with the wheel axis as shown in FIG. Since the wheel frame 5 is not restrained, the vehicle can move freely while making slight left and right turns. Since the actuating section 16 consisting of the friction frame mechanism 28 and the sliding frame mechanism 29 is adapted to the direction of rotation of the wheel 9, it does not interfere with normal rotation of the wheel 9.

As described above, when the traveling body 2 travels further in the opposite direction in a state in which the legs 7 are not restrained and the wheels 9 are running freely, the restrained state is changed to the unrestricted state. As in the case, the friction frame mechanism 28, especially the friction portion 33, receives frictional resistance from the side surface of the wheel 9, so the friction frame mechanism 28 rotates about the third shaft 32, but in both cases, the friction frame mechanism 28 rotates about the third shaft 32. When converting, everything stops once and then starts, especially when reversing, the friction frame mechanism 28
If the friction pieces 31, 31 are even slightly separated from the wheels 9, the friction frame mechanism 28 may not automatically rotate when the wheels 9 are reversed. However, the friction operation assisting mechanism 34 is pulled in the rotational direction of the wheel 9 and reliably assists the rotation of the friction frame mechanism 28. Then, when the wheel axle 8 is located on the forward side in the running direction relative to the rotation axis 4 and the wheel is reversed again, the leg piece 7 is reversed with the rotation axis 4 as a fulcrum due to the running force,
The claw portion 12 of the first engaging portion 10 slides on the upper edge 24 of the second engaging portion 17 and engages with the fitting groove 23, and the leg piece 7 converts its rotation into a restricted state. , the wheel frame 5 returns to its original state, but FIG. 6 shows the state just before the wheel frame 5 enters the restrained state. . Therefore, the traveling body 2 has the first engaging part 10 and the second engaging part 1.
7, the leg piece 7 travels in a rotationally restrained state.

The above description is of the first embodiment of the present invention, in which the base 3 is in the form of a flat plate. However, a second embodiment of the invention in which a pipe material is used as the base 3 is shown in FIGS. 9 to 11. In the above-described second embodiment, the leg piece 7 is rotatably provided at the lower end of the pipe-shaped base 3, and the swing drive unit 13 is also swingably provided inside the leg piece 7. This is the same as the first embodiment. However, in this second embodiment, a bracket 40 is attached to the pipe-shaped base 3, and the first engaging portion 10 is provided on the bracket 40. The bracket 40 has a first fixed frame 41 attached to one half of the base 3 and a second fixed frame 42 attached to the other half of the base 3,
The first fixed frame 41 and the second fixed frame 42 are rotatably connected at one side by a hinge mechanism 43. Also,
A fastening rod 44 consisting of a bolt and a nut is provided at the free end portion of the first fixed frame 41 and the second fixed frame 42, and when the fastening rod 44 is removed, the first fixed frame 41 and the second fixed frame 42 are fixed. The frame body 42 can be rotated to be attached to or removed from the base 3, and the bracket 40 can be firmly attached to the base 3 by tightening the fixing rod 44. In addition, there is a fixing hole 3' in the base 3.
By opening the bracket 40 and inserting the fixing bolt 45 from the first fixing frame 41 into the fixing hole 3', the bracket 40 can be more firmly attached to the base 3. In addition, the fixing hole 3
If the brackets 40 are provided facing each other in the radial direction of the base 3, it is possible to attach the bracket 40 to the base 3 without arbitrarily limiting the position of the first engaging portion 10 due to practical necessity. In the second embodiment of the present invention, the other configurations are the same as those in the first embodiment.

FIGS. 12 and 13 show a third embodiment of the present invention. In particular, the base 3 is made into a pipe shape similar to the second embodiment of the present invention described above, and a wheel is provided on one side of the leg piece 7. This is a case where the present invention is applied to a known wheel device 1 provided with 9 braking mechanisms 46 (two-dot chain lines in FIGS. 12 and 13). leg piece 7
With the braking mechanism 46 on one side, it would be impossible to install and operate a device such as that shown in FIG.
Since the swing drive unit 13 must be attached to the inside of the leg piece 7 so as to extend to the other side, the third embodiment has the swing drive unit 13 left and right reversed in contrast to the first embodiment of the present invention. The concrete configuration is as follows: In a conventional wheel device, when the inner frame swings in this way, the engagement/disengagement operation is reversed and it is impossible to install it, but in the case of the present invention. teeth,
The arc-shaped regulating groove 20 of the swing frame 14 is bored on the opposite side to that shown in the embodiments of FIGS. 1 to 10, and the first shaft 18 passes through it, and the second shaft 19 is used as the zero fulcrum shaft. It has expandability as it could be implemented by simply installing the spring material 21, and the other configurations are similar to those of the first embodiment of the present invention.
This is the same as the second embodiment. In the second and third embodiments of the present invention, the symbols shown in the drawings but not explained are the same as the structures of the same symbols in the first embodiment of the present invention, so the explanation will be omitted.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and can be implemented in any manner as long as the configuration described in the claims is not changed. Further, the wheel device 1 of the present invention is attached to the base 3 of the traveling body 2, but generally four wheel devices 1 are attached to one traveling body 2 on the front and rear, left and right sides. In this case, if all four wheel devices 1 are installed so that the first engaging portions 10 are in the same direction, all the wheel devices 1
is in a restricted state or in an unrestricted state. However, the two left and right wheel devices 1 and the other two left and right wheel devices 1 are arranged so that the first engaging portions 10 face inward facing each other, or the first engaging portions 10 are When attached to the base 3 of the traveling body 2 so as to face outward away from each other, the two wheel devices 1 on the forward side in the traveling direction of the traveling body 2 are in an unrestricted state, and the two wheel devices 1 on the rear side are in a restrained state. or vice versa, and the attachment state of the wheel device 1 to the traveling body 2 may be set in the most appropriate manner depending on the function and structure of the traveling body 2.

[0018]

Effects of the Invention: A wheel frame is provided at the base of the lower end of the traveling body so as to be able to rotate horizontally by a pivot shaft, and the center perpendicular of the pivot shaft and the lateral wheels supporting the wheels provided on the wheel frame. A first engaging portion is provided at the base portion with a constant distance from the center perpendicular line of the shaft, and a second engaging portion is provided inside the wheel frame to engage with and disengage from the first engaging portion. A rocking frame having an engaging portion, a fixed frame located inside the rocking frame and held by the wheel frame, and when the traveling body is running in the forward direction facing the side of the wheel. A swing drive unit is provided, which includes an operating unit that does not operate because the wheels are rotating in the forward direction, but operates when the traveling object runs in the opposite direction and the wheels rotate in reverse.The operating unit of the swing drive unit swings the swing frame. It is characterized in that the first engagement part and the second engagement part are engaged and disengaged through movement, so that the wheels can be reliably restrained no matter what structure the traveling body has. state or also converts to an unrestricted state. In particular, by making the swing drive unit 13 into a cassette shape, it is possible to attach it not only to the embodiments shown in FIGS. 12 and 13 but also to correspond to each conventional wheel configuration, including the flat plate shape of the base. Features of the invention 1
In addition, even if the wheels shake a little, or even if there is something attached to them or if they are worn out, they are housed inside the wheel frame as mentioned above, and the top surface of the traveling body Since it operates reliably without being affected by any load, it can be used in a significantly wider range of applications, increasing its practical value.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional side view of a first embodiment of the present invention in a restrained state.

FIG. 2 is a partially cutaway front view of the restrained state of the first embodiment of the present invention.

FIG. 3 is a longitudinal sectional side view immediately before the restraint state of the first embodiment of the present invention is released.

FIG. 4 is a front view of the first embodiment of the present invention when the restraint state is released.

FIG. 5 is a longitudinal sectional side view of the first embodiment of the present invention when the restraint state is converted to the non-restraint state.

FIG. 6 is a partially cutaway side view of the first embodiment of the present invention immediately before the device enters the restrained state from the unrestricted state.

FIG. 7 is a sectional view taken along line A-A in FIG. 1;

FIG. 8 is an exploded perspective view of the swing drive unit 13.

FIG. 9 is a side view of a second embodiment of the invention.

FIG. 10 is a front view of a portion of a second embodiment of the invention.

FIG. 11 is a cross-sectional plan view of a portion of a second embodiment of the invention.

FIG. 12 is a partially cutaway side view of the restraint state of the third embodiment of the present invention.

FIG. 13 is a partially cutaway side view of the third embodiment of the present invention in an unrestrained state.

[Explanation of symbols]

1 Wheel device 2 Running body 3 Base 4 Swivel axis 5 Wheel frame 6 Top part 7 Leg piece 8 Wheel axle 9 Wheels 10 First engaging part 11 Mounting frame 12 Claw part 13 Swing drive part 14 Swing frame 15 Fixed frame 16 Actuation part 17 Second engaging part 28 Friction frame mechanism

Claims (3)

[Claims] 1. A wheel frame is provided at the base of the lower end of the traveling body so that it can be horizontally rotated by a rotation axis, and a center perpendicular line of the rotation axis and a lateral wheel axis supporting the wheels provided on the wheel frame are provided. A first engaging portion is formed at the base, and a second engaging portion is disposed within the wheel frame and engages and disengages from the first engaging portion. A swinging frame having an engaging portion, a fixed frame located inside the swinging frame and held by the wheel frame, and a wheel when the traveling body is running in the forward direction facing the side of the wheel. A swing drive unit is provided, which includes an operating unit that does not operate because the wheels are rotating in the forward direction, but operates when the traveling body runs in the opposite direction and the wheels reverse, and the operating unit of the swing drive unit swings the swing frame. 1. A wheel device characterized in that the wheel device is configured to change engagement and disengagement between a first engagement portion and a second engagement portion by moving the first engagement portion and the second engagement portion. 2. The operating section includes a friction frame mechanism facing the side surface of the wheel, and a sliding frame mechanism that rotates together with the friction frame mechanism, in which the left and right sliding pieces of the sliding frame mechanism slide on the fixed frame. The wheel arrangement according to claim 1, facing the edge. 3. The wheel device according to claim 1, wherein the operating section is provided with a friction operation assisting mechanism that automatically assists the operation when the wheel rotates in reverse.