JP2921456B2 - Twin wheel casters - 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 two-wheel caster provided with a braking mechanism for stopping traveling and turning of the caster.

[0002]

2. Description of the Related Art A two-wheel caster provided with a braking mechanism for stopping traveling and turning has already been proposed by the present applicant (Japanese Utility Model Publication No. 7-33921). As shown in FIG. 17, the two-wheel caster includes an axle 4 for supporting both wheels 3, 3; a turning body (caster body) 2 for supporting the axle 4; And a vertical shaft 1 which is rotatably supported in the vertical direction at a position eccentric to the side. A notch groove 5 is formed to be recessed on the rear side in the traveling direction of the turning main body 2, and a through hole 7 is formed in the bottom surface of the notch groove 5 so as to penetrate in the vertical direction. The brake elevating rod (braking rod) 6 is inserted into the through hole 7. The braking elevating rod 6 is urged upward by a spring 8 stretched between the bottom surface of the head and an intermediate step portion of the through hole 7, and has a grounding piece (a braking part) made of an elastic material such as rubber at the lower end. ) 9 is attached via the cover 10.
Between both side walls of the notch groove 5, the brake lever 11 is
2 and is pivotably supported by the brake lever 1.
1 is engaged with the upper surface of the head of the braking elevating rod 6. The braking mechanism 20 is configured by the braking elevating rod 6, the spring 8, the grounding piece 9, and the braking lever 11.

When the brake lever 11 is in the non-braking position shown in FIG. 17, the lower side of the tip cam surface of the brake lever 11 is laid down along the bottom surface of the notch groove 5 and is attached by a spring 8 from below. It is held in contact with the top surface of the braking lift rod 6 that is urged. Then, the cover 10 is brought into contact with the lower surface of the cylindrical portion 13 and the grounding piece 9 is held above the floor surface. At the time of braking, the braking lever 11 is moved with respect to the pin 12 as shown in FIG.
When it is turned counterclockwise to stand up, the brake lever 11
Of the distal end cam surface presses the top surface of the braking elevating rod 6 to push the braking elevating rod 6 downward against the spring 8;
When the upper end surface of the end cam surface of the brake lever 11 comes into contact with the top surface of the braking elevating rod 6, the braking elevating rod 6 is held at the lower position by surface contact. At this lower position, the grounding piece 9 provided at the lower end of the braking elevating rod 6 is pressed against the floor surface, and the wheels and the turning of the casters are stopped.
When the brake is released, if the brake lever 11 is depressed with a foot or the like, the brake lifting / lowering rod 6 is urged upward by the spring 8 and returns to the inoperative position shown in FIG. I have. Thus, in the conventional twin wheel caster,
The grounding piece 9 is pressed against the floor surface to stop the wheel and stop turning.

[0004]

In the conventional two-wheel caster described above, the grounding piece 9 is pressed against the floor by operating the braking lever 11 to stop the wheel and stop the turning. 9 is pressed against the floor surface on the rear side in the traveling direction of the caster, so that it is grounded at a position away from the vertical shaft 1. For this reason, when a right or left force is applied to the vertical shaft 1 attached to the furniture or the like in the traveling direction, the vertical shaft 1 is free to turn with respect to the caster main body 2. Attempt to rotate to the center. On the other hand, the greater the frictional force between the grounding piece 9 and the floor surface, the greater the braking force can be kept. However, to increase the braking force, the frictional resistance of the grounding piece 9 and the grounding area and the grounding piece can be increased. The pressing force of No. 9 must be increased. However, since such a braking mechanism 20 is provided on the rear side in the traveling direction from the axle 4 in order to reduce the size of the caster itself, the contact area of the contact piece 9 and the resilience of the spring 8 are limited. When a force is applied to furniture or the like, the caster may turn, and there is a problem that the turning of the caster cannot be completely stopped.

The present invention has been made in order to eliminate the above-mentioned disadvantages, and an object of the present invention is to provide a two-wheel caster capable of reliably performing a wheel stopper and a turning stopper with a simple configuration.

[0006]

SUMMARY OF THE INVENTION A two-wheel caster according to the present invention comprises a caster body having both wheels rotatably supported via an axle, and a rotatable bearing mounted on a portion of the caster body offset from the axle. Vertical shaft, a brake rod inserted into a through hole formed in the bottom of the groove part cut off on the upper side opposite to the vertical axis with respect to the axle of the caster body, and this brake rod is resiliently biased upward. A spring, a brake unit attached to the lower end of the brake rod, and a tip cam surface abutting on the upper surface of the brake rod, pivotally supported in the notch groove, and projecting the operation unit outward. A two-wheel caster, which is provided with a brake lever that moves the brake rod up and down by operating the operation unit and presses and holds the brake unit at a lower ground contact position. And engaging means for engaging portions are formed along the circumferential direction, the braking portion and integrally lifting, elastically displaceable engaging vertically against the said engagement portion at the ground position of the brake lock A lock means having a portion is provided, and the running and turning of the caster are stopped by operating the operation portion.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to embodiments shown in the drawings. 1 is a longitudinal sectional view showing a two-wheel caster according to one embodiment of the present invention, FIG. 2 is a longitudinal sectional view showing a state of the two-wheel caster of FIG. 1 at the time of braking, and FIG. 3 is a main part of the two-wheel caster of FIG. 4 to 7 are partially cutaway rear views, longitudinal sectional views, plan views, and side views showing the caster body of the two-wheel caster of FIG. 1, respectively. FIG. 8 is a VIII-VIII line of the caster body of FIG. Cross-sectional view along FIG. 9,
Is a bottom view of a vertical axis, FIGS. 10 and 11 are side views and a partially cutaway rear view of a brake lever, respectively, FIG. 12 is a bottom view of a brake rod, FIG. 13 is a plan view showing a rotation stopper washer,
FIGS. 14 to 16 are a plan view, a rear view, and a longitudinal sectional view, respectively, showing a state in which a turning stopper is inserted into the braking portion. As shown in FIG. 1, the two-wheel caster 30 includes a caster main body 31 and an axle 3
And two rotatable wheels 33 rotatably supported via a second wheel 2, and rotatably in a mounting hole 34 formed vertically penetratingly formed at a position eccentric to the forward side in the traveling direction from the axle 32 of the caster body 31. And a fitted vertical shaft 35. On the upper part of the vertical shaft 35, a screw portion 35C to be screwed to the side of an attached body such as furniture (not shown) is formed. Vertical shaft 35
As shown in FIG. 9, the lower small-diameter portion 35A protrudes downward from the mounting hole 34, and the protruding end 35B of the small-diameter portion 35A has a non-circular cross-section (in this embodiment, ) Is formed.

As shown in FIGS. 4 and 5, a cut-out groove 36 is formed in the upper portion of the rear side of the caster body 31 in the traveling direction (opposite side of the vertical shaft 35 with respect to the axle 32). . A through hole 3 is formed in the bottom surface 36A of the notch groove 36.
7 are formed penetrating in the vertical direction. As shown in FIG.
As shown in FIG. 6 and FIG.
7A and a circular hole 37C formed in the bottom surface 37B of the spring receiving hole 37A. A braking rod 38 is inserted into the through hole 37 as shown in FIGS. The brake rod 38 has a square head section 38.
A and a rod body 38B.
B is inserted into the circular hole 37C, and the head 38A is accommodated in the spring accommodating hole 37A. The brake rod 38 is urged upward by a spring 39 stretched between a bottom surface of the head 38A and an intermediate step (that is, a bottom surface) 37B of the through hole 37, and has a lower end made of an elastic material such as rubber. A piece (braking unit) 40 is attached. Notch groove 36
The brake lever 41 is housed between the side walls 36C and 36D of the first arm 36 and is pivotally supported by a pin 42. As shown in FIGS. 1 and 2, the brake lever 41 has the distal end cam surfaces 43, 44 engaged with the upper surface of the head 38 A of the brake rod 38 and formed in an arc on the opposite side of the lower cam surface 43. The operated portion 45 projects rearward in the traveling direction of the notch groove portion 36.

The projecting end 35B of the vertical shaft 35 has
As shown in FIGS. 1 and 2, a turning stopper washer 50 as an engaging means is fitted and caulked. As shown in FIGS. 3 and 13, the rotation-stop washer 50 has a large number of concave grooves 51 as engagement portions which are recessed in the outer periphery in the radial direction at equal intervals. And, this turning stopper washer 50
As shown in FIGS. 1 and 2, a rotation stopper 53 as a locking means is provided between the brake rod 38 and the brake rod 38. The stopper 53 is made of an elastic material such as a metal leaf spring or plastic.
As shown in FIGS. 4 to 16, the mounting portion 54 formed at one end is embedded in the grounding strip 40. Rotation stopper 53
In the buried state, a non-circular (in this embodiment, a circular cut-out shape in parallel) hole 54A is arranged in the mounting hole 40A of the grounding strip 40. When the mounting portion 54 is buried in the grounding piece 40, a part of the grounding piece 40 fits into the other hole 54B of the mounting portion 54 and is locked to the grounding piece 40 (see FIG. 16). ) The non-circular hole 54A of the detent stopper 53 embedded in the grounding piece 40 is inserted into the lower end of the brake rod 38 and caulked.

The turning stopper 53 is attached to the mounting portion 54.
An arm 56 bent upward from above is provided, and an engagement claw 57 as a lock portion formed at the tip of the arm 56 is provided. The arm 56 is flexible and has a distal end that can be elastically displaced in the vertical direction. On both sides, protrusions 55 and 55 are formed near the engagement claws 57. The arm 56 is disposed inside walls 60, 60 formed below the caster main body 31, and both side projections 55, 55 of the arm 56 can contact the inner wall surfaces of the walls 60, 60. Therefore, when a force in the left-right direction (up-down direction in FIG. 3) is applied to the arm 56, one of the protrusions 55, 55 comes into contact with the inner wall surfaces of the wall portions 60, 60. The engagement claw 57 is formed so as to be able to fit into the concave groove 51 of the rotation stop washer 50. In the present embodiment, the section is formed in a substantially C-shaped cross section and is fitted into two adjacent concave grooves 51 at the same time.

As shown in FIG. 1, when the grounding piece 40 is at the non-braking position above the floor surface, the engagement claw 57 is held above the rotation stop washer 50, and When the piece 40 is lowered to a lower braking position in contact with the floor, the engaging claw 57 is fitted into the concave grooves 51, 51. When the grounding piece 40 descends, even if the engaging claw 57 does not fit while being displaced from the concave grooves 51, the arm 56 is bent so that the engaging claw 57 is pressed against the upper surface of the rotation stopper washer 50. Since the caster main body 31 and the vertical shaft 35 are relatively slightly swiveled, the engaging claw 57 slides on the upper surface of the swivel washer 50 so that the engaging claw 57 is automatically fitted into the nearby grooves 51, 51. Has become.

Next, the operation of the twin wheel caster according to the above configuration will be described. The caster 30 is in a non-braking state,
That is, in the free running and free turning states, FIG.
As shown in the figure, the operation unit 45 protruded rearward in the traveling direction.
Is pressed to swing the brake lever 41, so that the lower cam surface 43 is engaged with the upper surface of the head 38A of the brake rod 38. At this time, the brake rod 38 is urged upward by the spring 39 and the upper surface of the head 38A is in surface contact with the lower cam surface 43, so that the brake lever 41 has turned the lower cam surface 43 downward. The grounding piece 40 is held in a state in which the grounding piece 40 contacts the lower surface of the cylindrical portion 61 outside the circular hole 37C and is held above the floor surface. Then, since the turning stopper 53 is held at the upper position together with the grounding piece 40, the engaging claw 57 is held above the turning stopper washer 50, and the wheels 33 can freely travel.
The caster main body 31 is rotatable.

Next, in order to bring both the running and the turning into a braking state, as shown in FIG. 2, the lower part of the operating part 45 is pressed to be erected, and the braking lever 41 is displaced to a lower swinging position so as to be in a high position. The side cam surface 44 is engaged with the upper surface of the head 38A of the brake rod 38. The brake rod 38 is pushed downward against the spring 39, the grounding strip 40 is pressed against the floor surface, and the wheels 33 cannot rotate and the brake state is maintained. At this time, the upper cam surface 44 of the braking lever 41 pushes the lower surface of the grounding piece 40 downward (see reference numeral L in FIG. 2) below the grounding surface of the wheel 33, and the difference L from the grounding surface is reduced. Correspond to the pressure contact force on the floor surface and increase the frictional resistance. And
When the grounding piece 40 descends, the turning stopper 53 is also attached to the arm 5.
6 is lowered downward between the wall portions 60, 60, and the engagement claws 57 on the rotation stopper washer 50 are fitted into the concave grooves 51, 51, and the rotation is locked. At this time, even if the engaging claw 57 does not fit in the concave grooves 51 and 51 and hits the upper surface of the rotation-stop washer 50, the arm 56 is bent so that the engagement claw 57 is pressed against the upper surface of the rotation-stop washer 50. Since the caster main body 31 and the vertical shaft 35 are relatively slightly swiveled, the engagement claw 57 is
0 is automatically fitted into the concave grooves 51 near the slide. Furthermore, when the two-wheel caster 30 is in the locked state, even if a lateral load is applied to the attached body side and a turning force is relatively applied to the vertical shaft 35 and the caster main body 31, both are in the concave groove 51, 51 and engaging claw 5
7, so that the force is transmitted via the protrusions 55 provided in the vicinity of the rotation stop stopper 53.
No burden is placed on the arm 56 of the first embodiment.

Braking of wheels 33 and caster body 31
In order to release the turning lock again, the upper side of the operation unit 45 is pressed down to bring the brake lever 41 back to the upper return position when the brake lever 38 is returned to the upper return position, and the brake rod 38 is returned upward by the spring 39 and the grounding piece 40 is released. Move away from the floor surface and
7 is separated from the grooves 51 and 51 and returns to the upper position.
As described above, in the two-wheel caster according to the above configuration, at the time of braking, the ground piece 50 is pressed against the floor surface and the vertical shaft 35 is also locked at the same time, so that the two-wheel caster can be reliably locked. The operation unit 45
By performing the one-touch operation, the wheel stop and the turning stop can be performed at the same time, and the locks can be simultaneously released. In addition, since the turning lock performance is improved, it is difficult for the turning power about the axis of the braking rod 38 to be applied to the grounding piece 40, so the braking performance of the grounding piece 40 is also improved. In addition, the detent stopper 53 is connected to the brake rod 3.
8 and an engaging claw 57 that engages with the vertical shaft 35 side.
Is formed by the elastically deformable arm 56, so that when the two-wheel caster 30 is braked, a force is applied to the attached body side even if the engaging claw 57 does not fit into the concave grooves 51, 51 at one time. When the caster main body 31 is turned, the rotation stop washer 50 and the engagement claw 57 rotate relatively and are automatically locked, so that the locking can be reliably performed.

In the above embodiment, the groove 51 of the rotation-stop washer 50 is formed in a radially concave shape as shown in FIG. 13. However, the present invention is not limited to this. Needless to say, it is only necessary to adopt a configuration that incorporates. In addition, during non-braking, the two-wheel casters 30 bring the lower cam surface 43 into surface contact with the upper surface of the head 38A, and apply the braking rod 38 so that the grounding piece 40 contacts the lower surface of the cylindrical portion 61 outside the circular hole 37C. Has set the length of
The present invention is not limited to this, and the ground piece 40 may not be brought into contact with the lower surface of the cylindrical portion 61 outside the circular hole 37C only by bringing the lower cam surface 43 into surface contact with the upper surface of the head 38A.

[0016]

As described above, according to the present invention, the caster body having both wheels rotatably supported via the axle, and the caster body rotatably supported on a portion deviated from the axle. A vertical shaft, a brake rod inserted into a through hole formed in a bottom of a groove portion notched at the upper side opposite to the vertical axis with respect to the axle of the caster body, and resiliently biases the brake rod upward. A spring, a braking portion attached to a lower end of the braking rod, and a tip cam surface abutting on an upper surface of the braking rod, pivotally supported in the notch groove portion, and projecting the operating portion outward. A two-wheeled caster having a brake lever and moving the brake rod up and down by operating the operation unit to press and hold the brake unit at the lower ground contact position. To And engaging means for engaging portions are formed Wait, the braking portion and integrally lifting, locking portion elastically displaceable engaging vertically against the said engaging portion is formed by the ground position of the brake Locking means, and stopping the running and turning of the caster by operating the operation unit, the wheel stop and turning stop can be reliably performed by one-touch operation with a simple configuration. Moreover, the braking performance and the turning lock performance can be improved.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a twin wheel caster according to one embodiment of the present invention.

FIG. 2 is a longitudinal sectional view showing a state of the two-wheel caster of FIG. 1 during braking.

FIG. 3 is a bottom view showing a main part of the twin wheel caster of FIG. 2;

FIG. 4 is a partially cutaway rear view showing a caster main body of the twin-wheel caster of FIG. 1;

FIG. 5 is a longitudinal sectional view showing a caster main body of the twin-wheel caster of FIG.

FIG. 6 is a plan view showing a caster main body of the twin wheel caster of FIG.

FIG. 7 is a side view showing a caster main body of the twin wheel caster of FIG.

8 is a cross-sectional view of the caster main body of FIG. 7 taken along line VIII-VIII.

FIG. 9 is a bottom view of the vertical axis.

FIG. 10 is a side view of a braking lever.

FIG. 11 is a partially cutaway rear view of the brake lever.

FIG. 12 is a bottom view of the brake rod.

FIG. 13 is a plan view showing a rotation stopper washer.

FIG. 14 is a plan view showing a state in which a turning stopper is inserted into the braking unit.

FIG. 15 is a rear view showing a state in which a turning stopper is inserted into the braking unit.

FIG. 16 is a longitudinal sectional view showing a state in which a turning stopper is inserted into the braking unit.

FIG. 17 is a longitudinal sectional view showing a conventional two-wheel caster.

[Explanation of symbols]

 REFERENCE SIGNS LIST 30 twin wheel caster 31 caster main body 32 axle 33, 33 wheel 35 vertical shaft 35B vertical shaft lower portion 38 brake rod 39 spring 40 grounding piece (brake section) 41 brake lever 45 operation section 51 concave groove (recess) 50 rotation stop washer (engagement) Means) 53 Rotation stop stopper (Lock means)

Continuation of the front page (56) References JP-A-61-33302 (JP, A) JP-A-51-64251 (JP, A) JP-A-53-104945 (JP, A) JP-A-50-54049 (JP, A) JP-A-49-118141 (JP, A) JP-A-3-178804 (JP, A) JP-A-2-133905 (JP, U) JP-A-1-74902 (JP, U) JP-A 63-28507 (JP, U) Japanese Patent Publication No. 51-27331 (JP, B2) Japanese Patent Publication No. 51-27329 (JP, B2) Japanese Patent Publication No. 51-27330 (JP, B2) Japanese Patent Publication No. 53-41420 (JP, B2) B2) JP 7-23283 (JP, Y2) JP 48-13891 (JP, Y1) Patent 97347 (JP, C2) (58) Fields investigated (Int. Cl. ⁶ , DB name) B60B 33 / 00-33/04

Claims (6)

(57) [Claims] 1. A caster body having both wheels rotatably supported via an axle, a vertical shaft rotatably supported at a position deviated from the axle of the caster body, and a caster body with respect to the axle of the caster body. A brake rod inserted into a through hole formed in the bottom of the groove, which is notched at the upper side opposite to the vertical axis, a spring for resiliently urging the brake rod upward, and attached to a lower end of the brake rod. A brake lever having a tip cam surface abutting on the upper surface of the brake rod, and being pivotally supported in the notch groove so as to protrude the operation portion outward. In a two-wheel caster in which a braking rod is moved up and down by operation to press and hold a braking portion at a lower ground contact position, the two-wheel caster is attached to a lower portion of a vertical shaft protruding downward from a caster body and has an engaging portion formed along a circumferential direction. With means The braking portion and integrally lifting, elastically displaceable vertically against the said engagement portion at the ground position of the brake
Lock means formed with a lock portion that engages with
A two-wheel caster, wherein running and turning of the caster are stopped by operating the operation unit. 2. A caster body having both wheels rotatably supported via an axle; a vertical shaft rotatably supported at a position deviated from the axle of the caster body; and a caster body with respect to the axle of the caster body. A brake rod inserted into a through hole formed in the bottom of the groove, which is notched at the upper side opposite to the vertical axis, a spring for resiliently urging the brake rod upward, and attached to a lower end of the brake rod. A brake lever having a tip cam surface abutting on the upper surface of the brake rod, and being pivotally supported in the notch groove so as to protrude the operation portion outward. A two-wheel caster that moves the brake rod up and down by operation and presses and holds the brake unit at the ground contact position below, which is attached to the lower part of the vertical shaft that protrudes downward from the caster body, and has a plurality of recesses formed at equal intervals on the outer circumference. Stop A washer, and a turning stopper having one end attached to the braking portion and an engaging claw formed at the other end capable of engaging with the concave portion. the stopper is moved up and down together with the braking portion, twin wheel caster, wherein the stopping the pivoting elastically displaceable engaged thereby driving the caster vertically against the said recess in the ground position of the braking portion of the engaging claw. 3. A turning stopper having one end embedded in the braking portion and attached to the brake rod, an arm bent upward to be elastically displaceable up and down from the attaching portion, and a tip end of the arm. The two-wheeled caster according to claim 2, wherein the caster main body is formed with a formed engaging claw, and a wall portion for accommodating the arm is formed on the caster main body. 4. The two-wheel caster according to claim 3, wherein the turning stopper has projections on both sides of the arm that can contact the wall. 5. The engaging claw is of the claims 2 to 4, characterized in that it has at the same time shape that can engage a plurality of recesses
The two-wheel caster according to any one of the above. 6. The two-wheel caster according to claim 5, wherein the recess is formed by a recess formed by being radially recessed from an outer peripheral edge of the rotation stop washer.