JPH0829643B2 - Caster locking device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a caster, and more particularly to a caster lock device for stopping the turning of the caster and braking (rotation stop) of the wheels.

[0002]

2. Description of the Related Art An example of a conventional caster will be described. The caster is rotatably fitted in a traveling wheel, a caster body in which the wheel is rotatably supported via an axle, and a vertical hole provided at a position eccentric from the axle of the caster body. In addition, it is equipped with a vertical shaft fixed to the bottom of the object to be attached such as furniture, and normally the caster body freely swivels around the vertical shaft and the wheels rotate to run in any direction. Used as a flexible car possible. This caster is a locking device that both brakes the wheels (stops rotation) and stops the turning of the caster body so that it will not move freely after moving furniture etc. and installing it at a predetermined position. (A so-called double lock device) is provided. Also, for example, in a hospital bed, etc., if you want to freely rotate the caster body to move in any direction,
In some cases, it may be desirable to drive the vehicle in a certain direction without turning it.For this purpose, the wheels are allowed to rotate freely, the turning of the caster body is restricted, and only straight movement in a certain direction is performed. Casters equipped with a swivel lock device that can lock only the swivel so that the swivel can be performed are already known. As described above, the caster is configured such that either the swing lock device or the double lock device is added depending on the use of the attached body.

[0003]

In the conventional casters, even if the casters have the same basic structure, the double lock device and the swing lock device have no common structure. Depending on which one is provided, it is necessary to drastically change the component parts of the caster, to attach a separate member, etc., which complicates the structure and raises the cost.

The present invention has been made in order to eliminate the above-mentioned drawbacks, and has a device for locking the rotation of casters only.
Caster that locks both turning and wheel rotation at the same time, so that it can be applied to any locking device by just replacing some parts by sharing the configuration with a so-called double locking device. It is an object of the present invention to provide a locking device of the above.

[0005]

A caster locking device according to the present invention comprises a caster body and wheels rotatably supported on the caster body via an axle.
A caster fixed to a mounted object such as furniture so as to be swingable, a swing lock member supported by the caster body so as to be able to move up and down, and a spring that constantly biases the swing lock member downward. An operating member for raising the swing lock member, a lock plate fixed to the mounted body side, having a swing lock engaging portion for engaging the swing lock member when the swing lock member rises, the swing plate A wheel lock member that is detachably attached to the lock member and that moves up and down integrally with the turning lock member; and a wheel lock member that is formed on the wheel and that engages with a braking portion provided on the wheel lock member when the wheel lock member rises And a wheel-side braking unit that stops the traveling of the wheels.

[0006]

In the caster lock device described above, when the swing lock member is raised by the operating member, the swing lock member that has risen against the spring engages with the swing lock engaging portion formed on the lock plate and the caster is locked. Lock the swing of the body. Also, when the swing lock member rises,
The wheel lock member also rises integrally, and the braking portion provided on the wheel lock member engages with the braking portion on the wheel side to lock the wheel. Moreover, the wheel lock member can be attached to and detached from the turning lock member, and if the wheel lock member is replaced with a wheel lock member that does not have a braking portion, the turning lock can be performed without locking the wheels.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the embodiments shown in the drawings. FIG. 1 is a vertical cross-sectional view of a caster 4 equipped with a lock device (generally indicated by reference numeral 1) according to an embodiment of the present invention, FIG. 2 is an enlarged cross-sectional view of a main portion thereof, and FIG. This lock device 1 can be used as either a swing lock device or a double lock device by simply replacing a lock fitting described later. The caster 4 is the caster body 6
The wheels 8 rotatably supported on the caster body 6 via the axle 2 and the caster body 6 on the axle 2
And a vertical shaft 10 rotatably fitted in a vertical mounting hole formed eccentrically. The caster 4 of this embodiment is a twin-wheel caster, and two wheels 8A and 8B are rotatably supported on both sides of the axle 2, and the vertical shaft 1
0 is located between these wheels 8A and 8B. The vertical shaft 10 has a lower portion fitted in the mounting hole of the caster body 6 as described above, and an upper portion having a threaded portion 10a screwed to the mounted body 2 (not shown) side of furniture or the like. Is formed, and a flange portion 10b for rotating the vertical shaft 10 when fixing the vertical shaft 10 is provided at an intermediate portion thereof. The flange portion 10b has a shape in which both sides of a circle are flatly cut out, and a tool such as a spanner is engaged with the flat surface 10c to rotate the flange portion 10b so that the threaded portion 10a is attached to the mounted body 2
Fasten to the nut fixed on the bottom of the. It goes without saying that the insertion portion of the vertical shaft 10 into the mounting hole of the caster body 6 is provided with a stopper.

When the caster body 6 is fixed to the mounted body by screwing the vertical shaft 10, the lock plate 12 is sandwiched between the flange portion 10b and the bottom surface of the mounted body to be fixed integrally. . As shown in FIGS. 4A and 4B, the lock plate 12 is made of an oval plate, and has a through hole 12a into which the vertical shaft 10 is inserted and a tip portion of a turning lock pin 14 described later. A lock hole (swing lock engaging portion) 12b into which 14a is fitted is formed. In addition, a positioning convex portion 12c is formed on a line passing through the centers of the through hole 12a and the lock hole 12b, and the convex portion 12c is fitted into a concave portion provided in a mounted object such as furniture. Thus, the lock plate 12 and the mounted body are positioned.

A vertical hole 16 is formed in a central portion of the caster body 6, that is, substantially above the axle 2 between the wheels 8A and 8B on both sides, and the swing lock pin (swing lock member) 14 is fitted therein. ing. This vertical hole 16 is
6a has a large diameter, and the lower portion 16b has a small diameter. The inner diameter of the small diameter portion 16b substantially matches the outer diameter of the turning lock pin 14, and the turning lock pin 14 slides up and down on the inner surface of the small diameter portion 16b. Below the small diameter portion 16b of the vertical hole 16, a square hole 18 that penetrates the caster body 6 in parallel with the axle 2 is formed, and the lower portion 14c of the swing lock pin 14 projects into the square hole 18.

A lock fitting (wheel lock member) 20 made of a rectangular plate is fitted to the lower portion 14c of the swivel lock pin 14 protruding into the square hole 18 so as to be vertically movable. The lock fitting 20 is designed so as not to fall off from the turning lock pin 14 by fitting a snap ring 22 into a groove formed in the lower end portion of the turning lock pin 14 (see FIG. 2). This lock metal fitting 20 and square hole 1
The first compression spring 24 is arranged between the upper surface of the pivoting member 8 and the upper surface of the pivot member 8 and always biases the swing lock pin 14 downward through the lock fitting 20. Also, slightly below the upper end portion 14a of the swing lock pin 14, the upper large diameter portion 16 of the vertical hole 16 is provided.
An enlarged diameter portion 14b having an outer diameter substantially matching the inner diameter of a is formed. A second compression spring 26 is arranged between the lower surface of the enlarged diameter portion 14b and the bottom surface of the large diameter portion 16b of the vertical hole 16 to constantly urge the swing lock pin 14 upward. The first spring 24 has a spring force of a strength that compresses the second spring 26 and pushes down the swing lock pin 14.

In this embodiment, the lock fitting 20 is shown in FIG.
Further, as shown in FIG. 6, it has an intermediate plate portion 20a and serration portions (braking portions) 20b on both sides thereof, and its longitudinal direction (the horizontal direction in FIG. 5) corresponds to the vertical direction of the paper surface of FIG. The square holes 18 are arranged so as to face each other. The insertion hole 20c is provided at the center of the intermediate plate portion 20a.
Is formed, and the turning lock pin 14 is inserted into the insertion hole 20c. The lock fitting 20 includes wheels 8A and 8A whose plate portion 20a has a length w _{1 of} approximately two.
The intervals between the wheels B coincide with each other, and the serration portions 20b provided on both sides of the plate portion 20a are located in the space inside the wheels 8A and 8B.

On the other hand, as shown in FIGS. 7 and 8, a rim 8A is provided on the inner surfaces of the wheels 8A and 8B facing each other.
Serration (wheel side braking part) 8 on the inner peripheral surface of a, 8Ba
Ab and 8Bb are formed. In addition, the outer periphery of the serration portion 20b of the lock fitting 20 is fixed to both wheels 8A and 8A.
The serrations 8Ab and 8Bb of B are formed of an arc substantially matching the radius r _{1 of the} portion. Therefore, when the lock fitting 20 rises together with the swing lock pin 14, the serration portion 20 b of the lock fitting 20 is locked.
Engages with the serrations 8Ab, 8Bb of the wheels 8A, 8B to stop the rotation of the wheels 8A, 8B.
When is lowered, the serration portion 20b is disengaged from the serrations 8Ab and 8Bb of the wheels 8A and 8B, so that the wheels 8A and 8B can freely rotate.

A swinging metal fitting 28 is provided below the swing lock pin 14.
One end 28a of the is arranged. This swing fitting 28 is
The caster body 6 swings around a first fulcrum pin 30 supported on the rear side of the swing lock pin 14 (to the right in FIG. 1), and the one swing end 28a.
Comes into contact with the lower end of the swing lock pin 14 from below, and the other swing end 28b comes into contact with a stop lever (operation member) 32 described below.

The stop lever 32 has a height substantially the same as that of the first fulcrum pin 30 and is supported by the caster body 6 on the rear side (right side in FIG. 1) of the fulcrum pin 30. It is rotatably supported by two fulcrum pins 34. The stop lever 32 contacts the upper surface of the right side end 28b of the swing member 28, and the cam portion 3 is in contact with the upper surface.
The caster body 6 has an operation portion 32b extending outward from the groove 6a cut out in the center of the caster body 6.

The cam portion 32a is provided when the operation portion 32b on the outer side is in a substantially horizontal position as shown by the solid line in FIG.
Release-side cam surface 32c that comes into contact with the upper surface of the swing fitting 28
As shown by an imaginary line in the figure, the lock-side cam surface 32d that comes into contact with the upper surface of the rocking fitting 28 when the operating portion 32b is in a position rotated approximately 90 degrees clockwise from the position indicated by the solid line. And have. The distance between the lock side cam surface 32d and the center of the second fulcrum pin 34 is equal to the release side cam surface 3
It is larger than the distance between 2c and the center of the second fulcrum pin 34. Therefore, when the release side cam surface 32c faces downward (upper surface side of the rocking fitting 28), the lower end of the swing lock pin 14 biased downward by the first spring 24 causes the rocking fitting 28 to move. The left end 28a is pushed downward and its right end 28b abuts on the release side cam surface 32c to be in a substantially horizontal state. When the lock-side cam surface 32d faces downward, the right end 28b of the rocking fitting 28 is pushed downward by the lock-side cam surface 32d, and the turning lock pin 14 is pushed up by the left end 28a. Has become. Moreover, the release side cam surface 32c and the lock side cam surface 32d are almost 90
Since there is an angle of degrees, which cam surface 32c, 3
Even when 2d hits the right end portion 28b of the swinging fitting 28, it is stably held at that position.

The operation of the caster lock device 1 having the above configuration will be described. When the caster 4 can be freely swiveled and the wheels 8A and 8B are allowed to rotate freely, the operation portion 32b of the stop lever 32 is lifted up to the state shown by the solid line in FIG. Then, since the release side cam surface 32c of the cam portion 32a of the stop lever 32 faces the lower swing metal fitting 28 side, the right end side 28b of the swing metal fitting 28 does not have a pushing down force.
The swing lock pin 14 is pushed down via the lock fitting 20 by the spring force of the first spring 24, and further, the left end side 28a of the swing fitting 28 is swung downward by the lower end portion of the swing lock pin 14, The right end portion 28b contacts the release side cam surface 32c of the stop lever 32. As a result, the upper end portion 14a of the swing lock pin 14 comes out downward from the lock hole 12b of the lock plate 12,
Since it comes to a position where it does not interfere with this lock plate 12,
The caster 4 can freely rotate. Further, since the lock fitting 20 is pushed down together with the turning lock pin 14 by the first spring 24, the serration portions 20b formed on both ends of the lock fitting 20 and the serrations 8Ab, 8Bb formed on the inner peripheral surfaces of the wheels 8A, 8B are separated. The meshing is disengaged and the wheels 8A and 8B can freely rotate and travel.

On the other hand, when turning and locking the rotation of the wheels are to be performed, the operating portion 32b of the stop lever 32 is rotated downward to the state shown by the phantom line in FIG. Then, the lock-side cam surface 32d of the cam portion 32a faces the lower swing fitting 28 side, pushes down the right end 28b of the swing fitting 28, and moves the left end 28a upward with the fulcrum pin 30 as the center. Rock. As a result, the swing lock pin 14
Also, the lock fitting 20 compresses the first spring 24 and ascends. When the lock plate 12 is accidentally located right above the swing lock pin 14 at the time of this ascent, the upper end portion 14a of the swing lock pin 14 is locked by the lock plate 12.
The caster 4 is immediately inserted into the lock hole 12b, and the turning of the caster 4 is immediately stopped. Normally, the positions of the swing lock pin 14 and the lock hole 12b do not match, so the swing lock pin 1
Even if 4 is raised, the caster 4 can still turn and continues to turn. Casters 4 turn to turn lock pin 14
When the tip portion 14a of the spring hits the lock plate 12, the swing lock pin 14 is supported from below by the weak spring force of the second spring 26.
6 is bent to descend slightly and enter the lower surface side of the lock plate 12. After that, when the tip end portion 14a of the turning lock pin 14 comes to the position of the lock hole 12b, it rises due to the action of the spring 26 and is fitted into the lock hole 12b to be caster 4
Is stopped (see FIG. 9). In this way, regardless of where the caster 4 is turning, the stop lever 32
By operating, it is possible to securely lock the turning while rotating 360 degrees at the maximum.

When the swing lock pin 14 is lifted by swinging the swing fitting 28 in the clockwise direction in FIG. 1 as described above, the washer 2 crimped to the lower end of the swing lock pin 14 is raised.
The lock metal fitting 20 is also lifted up via 2. Serration portions 20b are formed on both ends of the lock fitting 20, and the wheels 8A, 8A
Meshes with serrations 8Ab and 8Bb formed on B,
The wheels 8A and 8B are braked (stopped rotation). In this way, by operating the stop lever 32 one by one, it is possible to double lock the turning stop and the traveling stop. Moreover, since the turning lock mechanism and the rotation lock mechanism of the wheels 8A and 8B are arranged on the same axis, the structure of the double lock device can be extremely simplified.

In this embodiment, the lock fitting 20 has the turning lock pin 14 penetrating into the central insertion hole 20c,
A snap ring 22 is attached to the lower end of the swing lock pin 14.
The lock lock pin 14 is prevented from coming off by being fitted. Therefore, for example, FIG. 10 and FIG.
A lock metal fitting 120 having a different structure as shown in FIG. 1 is prepared, and when the caster 4 is assembled, the lock metal fitting 12 is used.
If 0 is attached to the swing lock pin 14, the wheels 8A, 8B
The rotation of can be set to be free and only the turning can be locked. This lock fitting 120
A plate portion 120a having an insertion hole 120c in the center
It does not have serrations on both sides. Therefore, even if the turning lock pin 14 is raised and the tip portion 14a thereof is fitted into the lock hole 12b of the lock plate 12 to lock the turning, the lock fitting 120
Since there is no serration portion 120b, the wheels 8A,
The traveling of 8B is not stopped, and the traveling can be performed only in a fixed direction in which the turning is locked. Further, when the wheels 8A and 8B are not braked in this way and only the turning lock is performed, the serrations 8Ab and 8Bb on the wheels 8A and 8B side are not necessary. , You can get a lower cost caster. The lock fitting 20 shown in FIG. 3 is designed to move up and down between the position shown by the broken line and the position shown by the chain double-dashed line.
0 indicates that the left side of the drawing is provided with the serration portion 20b, and that the right side of the drawing is not provided with the serration portion.

As described above, the caster 4 having only the turning lock mechanism and the caster 4 having the double lock mechanism for both the turning lock and the wheel braking are
Since the other parts can be assembled by using the common parts only by exchanging the individual parts (the lock fittings 20, 120), the caster 4 having an extremely low cost can be obtained. Moreover, the structure of the double lock mechanism can be simplified. In the above embodiment, the vertical shaft 10 is used as a means for attaching the caster 4 to an object to be attached such as furniture, but the present invention is not limited to this, and it can be turned freely via a disc-shaped attachment seat. Even in the case of the mounting structure, the same function can be obtained by caulking the lock plate together with the mounting seat.

12A and 12B show another example of the lock plate 112.
12 has a plate shape longer than the lock plate 12 of the above-mentioned embodiment, a through hole 112a of the vertical shaft 10 and a positioning convex portion 112c are formed in the central portion thereof, and lock holes 112b are formed at both ends thereof. Are formed. In this lock plate 112, two lock holes 112b are formed at symmetrical positions with respect to the through hole 112a. Therefore, in the case of locking the turning, in the case of the lock plate 12 according to the above-described embodiment, the maximum is possible. It was supposed to be locked after rotating 360 degrees, but this lock plate 1
With 12, the swivel is automatically locked by a maximum rotation of 180 degrees.

13 (a) and 13 (b) show a third example of the lock plate 212. The lock plate 212 has a through hole 212a for the vertical shaft 10 and a projection for positioning in the center of the circular plate. A part 212c is formed,
A large number of lock holes 212b are provided on the outer periphery at equal intervals in the circumferential direction.
Are formed. By using this lock plate 212, it is possible to lock the turning at any position. The lock plates 12, 112, 212
In each case, the lock hole 1 is used as the swing lock engaging portion.
2b, 112b, 212b are provided, but not limited to this,
It is also possible to form a protrusion on the lower surface side and engage the tip portion 14a of the swivel lock member (swivel lock pin 14) that has risen.

[0023]

As described above, according to the present invention, the lock member of the caster is supported by the caster body so as to be lifted and lowered, and the spring for constantly biasing the swing lock member downward. An operating member that raises the swing lock member, a lock plate that is fixed to the mounted body side and that has a swing lock engaging portion that engages with the swing lock member when the swing lock member rises, and the swing lock. A wheel lock member that is detachably attached to the member and that moves up and down integrally with the turning lock member; and a wheel lock member that is formed on the wheel and that engages with a braking portion provided on the wheel lock member when the wheel lock member rises. The wheel lock member attached to the turning lock member does not have a braking unit but a braking unit. It is replaced with a wheel locking member having no, it is possible to change the mechanism for locking the pivoting only double lock mechanism.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a caster lock device according to an embodiment of the present invention.

FIG. 2 is an enlarged cross-sectional view showing a structure of a lower part of a lock fitting and a lock pin.

FIG. 3 is a right side view of the lock device of the caster.

4A is a plan view of a lock plate used in the lock device, and FIG. 4B is a vertical sectional view thereof.

FIG. 5 is a plan view of a lock fitting used in the lock device.

FIG. 6 is a right side view of FIG.

FIG. 7 is a view showing an inner surface side of a wheel of a caster provided with the lock device.

FIG. 8 is a vertical sectional view of a wheel of a caster provided with the lock device.

FIG. 9 is an explanatory diagram showing a process of locking turning by the lock device.

FIG. 10 is a plan view showing a different lock fitting.

11 is a right side view of FIG. 9. FIG.

12A is a plan view showing a different example of the lock plate, and FIG. 12B is a vertical sectional view thereof.

13A is a plan view showing still another example of the lock plate, and FIG. 13B is a vertical sectional view thereof.

[Explanation of symbols]

1 Caster Lock Device 2 Axle 4 Caster 6 Caster Body 8A Wheel 8B Wheel 8Ab Wheel Side Braking Part (Serration) 8Bb Wheel Side Braking Part (Serration) 12 Lock Plate 12b Swing Lock Engagement Part (Lock Hole) 14 Swing Lock Member (Turning lock pin) 20 Wheel lock member (lock fitting) 20b Engagement portion of wheel lock member (serration portion of lock fitting) 24 Spring (first spring) 32 Operation member (stop lever)

Claims (5)

[Claims] 1. A caster having a caster main body and wheels rotatably supported on the caster main body via an axle, the caster fixed to a mounted object such as furniture so as to be rotatable, the caster main body being movable up and down. A swing lock member supported by the spring, a spring that constantly urges the swing lock member downward, an operating member that raises the swing lock member, and a swing lock member that is fixed to the mounted body side and that moves when the swing lock member rises. A lock plate formed with a turning lock engaging portion with which the turning lock member engages, a wheel lock member that is detachably attached to the turning lock member, and moves up and down integrally with the turning lock member, and formed on the wheel. And a wheel-side braking unit that engages with a braking unit provided on the wheel locking member to stop the traveling of the wheel when the wheel locking member rises. Ter of the locking device. 2. The lock device for a caster according to claim 1, wherein the lock plate is provided with a plurality of swing lock engaging portions with which the swing lock member is engaged. 3. The caster lock device according to claim 2, wherein the lock plate has a disc shape and a large number of swing lock engaging portions are formed on the circumference of the lock plate at equal intervals. 4. The wheel lock member according to claim 1, wherein a wheel lock member having a braking portion that engages with a wheel side braking portion and a wheel locking member not having a braking portion can be exchanged. Caster locking device. 5. The caster lock device according to claim 4, wherein a wheel provided with a wheel side braking portion and a wheel provided with no wheel side braking portion can be exchanged.