JPH0425161B2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field]

The present invention mainly relates to an improvement of a caster with a braking device attached to a medical bed or the like.

[Conventional technology]

For casters used for medical beds, etc., when fixed indoors, it is necessary to securely lock the rotation and rotation of the wheels and keep them stationary at a fixed position. The wheels must be able to rotate and turn freely, and when traveling long distances in a straight line, it is easier to use the wheels if they are configured to rotate while restrained in the straight direction. well,
As a caster with such a braking device, Tokkosho
No. 50-7336 is known. This caster houses a cam, a bearing pin, a locking pin, etc. in a casing consisting of two halves, and when the cam is rotated, the locking pin is lowered to lock the turning and rotation of the wheel. It is composed of Then, when assembling the casing, the pair of left and right split bodies are combined and the upper and lower ends are joined by rings to form an integral body. In this type of caster with a brake device, the locking pin must be installed in an accurate position because the locking pin is lowered by the rotational displacement of the cam and the head of the locking pin and the brake are engaged with each other. For this purpose, a locking nut is screwed onto the locking pin under the cap nut that abuts against the cam surface to enable adjustment.

[Problems to be solved by the invention]

However, after the above-mentioned members are housed in the casing, there is a drawback that the height of the locking pin cannot be finely adjusted because the casing is integral. Therefore, if the casing is divided into upper and lower halves, and the two are made into double pipes at the joining part, and screws are provided on the opposing surfaces so that they can be screwed together, the height of the lock pin can be adjusted by adjusting the screws. On the other hand, the locking pin is conventionally formed into a square bar so that it does not rotate within the casing, so when a coil spring is fitted on the outside of the locking pin and a threaded part of the casing is formed, the outer circumference of the casing increases. There are drawbacks to this. As mentioned above, this caster is used for medical beds and the like, and since the casing is fitted into the pipe that serves as the support leg, the outer circumference cannot be set large. Therefore, if the locking pin is a round bar, the coil spring can be fitted closely and the outer circumference can be set small, but the locking pin rotates within the casing and has the disadvantage that it cannot stop the wheel from turning. This invention was devised in view of the above circumstances, and the main problem is that the casing is divided into upper and lower halves and the two are connected with screws so that the height can be adjusted, and a round rod-shaped locking pin is used. To provide a caster with a braking device capable of restraining a lock pin from turning even when the gear is turned.

[Means to solve the problem]

In order to achieve the above-mentioned problems, this invention fixes a hollow cylindrical casing so that its lower end penetrates the fixed base plate 8 and protrudes downward, and also includes a rotating base plate below the fixed base plate 8. 1 is rotatably mounted via a radial ball bearing, and a support yoke 1' is connected to the swivel base 1, and a wheel 2 is mounted at the tip.
A cam 25 is built into the hollow upper part of the casing, and the lock pin is biased upward so that its upper end contacts the cam 25. 15 is provided to be slidable up and down in the hollow of the casing,
A rotating lock plate 2 is attached to the lower end of the lock pin 15.
0 are interlockably provided, and the lock pin 15 engages with the second engaging portion 5c of the stopper 5 provided on the swivel base 1 in the halfway lowered position to lock the rotation of the swivel base 1. The receiving portion 20d and the first engaging portion 4c of the brake plate 4 provided on the rotating platform 1 at the position where the lock pin 15 is further lowered.
The engagement receiving portion 20a is connected to the rotating lock plate 20.
In a caster equipped with a control device in which the bottom surface of the brake plate 4 can brake the wheel 2 by the thrust of the lock pin 15, (a) the casing is divided vertically into an upper sleeve 13 and a lower sleeve 12; Sleeve 13
One of the lower ends and the upper end of the lower sleeve 12 is fitted onto the other, and each screw 13 is inserted in the axial direction on the opposing surface.
(b) In the upper part of the lower sleeve 12, there is a spring insertion chamber 12b with a larger diameter than the hollow part along the inner wall of the lower sleeve 12.
(c) The coil spring S is fitted onto the lock pin 15, and its upper end abuts against the protrusion 16 of the lock pin 15, causing the lock pin 15 to be attached upward. (d) The turning lock plate 20 is formed with an engaging recess 20c that is a recess or hole that opens upward. (e) A rotation preventing member 11 having a leg portion 11a hanging from the lower sleeve 12. are provided integrally, and the leg portion 11a is slidably engaged with the engagement recess 20c.

[Effect]

The height of the upper sleeve 13 can be adjusted by screwing forward and backward the threaded portions of the screws 13s and 12s of the upper sleeve 13 and lower sleeve 12 that constitute the casing. This upper sleeve 13 has a built-in cam 25 that is pressed from below by a lock pin 15 that is biased upward and whose upper end abuts against the upper sleeve 13. The cam 25 moves up and down in conjunction with the displacement, making it possible to finely adjust the position of the rotating lock plate 20 provided at the lower end of the lock pin 15 in the vertical direction via the lock pin 15. On the other hand, since the spring insertion chamber 12b is expanded along the inner wall in the upper part of the lower sleeve 12 and contains the coil spring S, the hollow space of the upper and lower sleeves 13, 12 can be maintained at a small diameter. Therefore, the height adjustment screws 13s and 12s are provided at the overlapping portion of the upper sleeve 13 and the lower sleeve 12.
Even if the casing is provided, there is no need to set the diameter of the casing large, and the casing can be fitted and fixed into the hollow of the pipe P which is set to a predetermined diameter and serves as the support leg of a medical bed or the like. Further, the turning lock plate 20 is formed with an engaging recess 20c that opens upward.
Since at least a portion of the leg portion 11a of the anti-rotation member 11 in the length direction is always inserted into the rotation lock plate 2, the lock pin 15 is a round bar.
Even if a force in the rotation direction is applied to the rotation stopper 1
The lower sleeve 1 is fixed to the lower sleeve 1 through the lower sleeve 1.
2, and the rotation of the rotation lock plate 20 can be restrained.

【Example】

A preferred embodiment of a caster with a braking device according to the present invention will be described below with reference to the drawings. As shown in FIGS. 1 to 3, this caster has a fixed base 8 on which a casing consisting of an upper sleeve 13 and a lower sleeve 12 is erected, and a support yoke 1' that pivotally supports a wheel 2. The base plate 1 is rotatably connected to the base plate 1 via a radial ball bearing. That is, reference numeral 1 is a rotating platform having bearing surfaces for ball bearings formed on the upper and lower sides, and a support yoke 1' extending downward is connected on both left and right sides of the rotating platform, and a wheel 2 is attached to the free end of the rotating platform. It is freely pivoted. A shaft 3 is inserted and suspended between both side plates of the tip portion 1a of the support yoke 1'. Further, a brake plate 4 having a bifurcated leg portion 4a is swingably supported on the shaft 3, and the bottom surface of the brake plate 4 serves as a braking surface and faces the outer peripheral surface of the wheel 2. It is curved so that it touches without any gaps, and in order to increase the braking effect,
A plurality of grooves 4b are formed in the width direction. Further, on the upper surface side of this brake plate 4, a first engaging surface 4c consisting of fan-shaped ratchet teeth is formed as a first engaging portion at the base of the leg portion 4a. The brake plate 4 is pivotally attached to the shaft 3 by inserting the shaft 3 into the insertion hole. Further, a bifurcated stopper 5 is pivotally mounted between the legs 4a, 4a of the brake plate 4 coaxially with the shaft 3 of the brake plate 4, and the tip of the stopper 5 serves as a second engaging part. A tabular claw portion 5a is integrally formed, and this stopper 5 is always biased clockwise in FIGS. 1 and 3 via a coiled spring 6, so that the top portion 5b of the stopper 5 The claw portion 5a is always held horizontally by contacting the lower surface of the board 1. Next, a fixed base plate 8 and a lower plate 7, which sandwich the above-mentioned rotating base plate 1 above and below and serve as an upper plate, are fixed to a lower sleeve 12 that passes through them. A bearing surface for a ball bearing is formed on the upper surface of each of the bearings. Balls 9 are arranged annularly between the fixed base plate 8 and the rotating base plate 1, and between the rotating base plate 1 and the lower plate 7, respectively.
9 are arranged in a row to form radial ball bearings in two stages, upper and lower, and the rotating base plate 1 is rotatably attached to the fixed base plate 8. In the figure, reference numeral 8' denotes an auxiliary piece that is fitted into the curved recess of the fixed base plate 8 and fixed to form a horizontal upper surface that is connected to the fixed base plate 8. Reference numeral 11 in the figure is a rotation preventing member, and as shown in FIG.
11a, 11a are vertically arranged at equal intervals, and are set to a length that allows the tip to be inserted into the engagement recess 20c even if the turning lock plate 20, which will be described later, is lowered by the rotational displacement of the cam 25, and the upper surface A hexagonal square hole 11b is formed in the hole 11b. Then, as shown in FIG. 7, the lower sleeve 12
The above-mentioned auxiliary piece 8' is attached to the step part formed in an annular shape below the
The fixed base plate 8, the lower plate 7, and the anti-rotation member 11 are fitted in sequence, and the lower end 12a of the lower sleeve 12 is caulked outward so as to abut against the inner peripheral surface of the anti-rotation member 11. Each member is integrally fixed to the lower sleeve 12. Further, a spring insertion chamber 12b having a larger diameter than the hollow space is formed on the inner circumferential surface of the center hole of the lower sleeve 12 and expands in the axial direction, and a coil spring S is inserted into this chamber.
is inserted. Further, an upper sleeve 13 is connected to the upper part of the lower sleeve 12 by screwing. That is, as shown in FIGS. 1 and 3, the upper end of the lower sleeve 12 is set to have a small diameter and extends upward so that the lower end of the upper sleeve 13 fits onto and overlaps the upper end of the lower sleeve 12. A screw is carved along the axial direction on its outer periphery. On the other hand, the upper sleeve 13 should correspond to this screw.
Since a screw is carved into the inner peripheral surface of the lower end of the upper sleeve 13, by rotating the upper sleeve 13, the upper sleeve 1
3 can be connected to the lower sleeve 12 in a height-adjustable manner. A pair of rectangular windows 14 are formed on the upper side surface of the upper sleeve 13, and a pair of camshaft insertion holes are formed perpendicularly to the windows 14. Reference numeral 15 denotes a lock pin in the shape of a round bar that passes through the lower sleeve 12 and the upper sleeve 13 and moves up and down, and an adjustment nut 17 and a cam nut 18 are screwed onto the upper part of the lock pin 15 via a washer 16. This lock pin 15 is always urged upward by the coil spring S. Further, at the lower end of the lock pin 15, there is a turning lock plate 2 that engages with the rotation prevention member 11.
0 is fixed. As shown in FIGS. 4 and 5, this turning lock plate 20 is formed into a substantially disk shape, and is gently tapered from the center of the lower surface of the turning lock plate 20 toward the outer periphery. A first engagement receiving surface 20a consisting of ratchet teeth is formed radially on the tapered lower surface of the swing lock plate 20. On the other hand, the upper surface of this turning lock plate 20 has four ribs 20b, 20b, 20 projecting radially.
An engagement recess 2 is formed between these ribs via b, 20b.
0c, 20c, 20c, 20c are recessed, and a pair of diametrically opposed notches 20d, 20 are provided on the outer peripheral edge of the lock plate 20.
d is formed to serve as a second engagement receiving portion, and the claw portion 5 of the stopper 5 is inserted into the notch portions 20d, 20d.
a is elastically engaged, locking the turning of the caster and allowing the wheel 2 to move straight. Therefore, the lower end of the lock pin 15 is inserted into the circular center hole of the swing lock plate 20, and the leg portion 1 of the rotation prevention member 11 is inserted into the center hole.
1a into the engagement recess 20 of the lock plate 20.
d, 20d, .
It is fixed to the lower end of 5. With the above-described structure, the lock plate 20 is connected to the upper and lower sleeves 12 through the rotation prevention member 11.
Rotates integrally with 13. Note that the first engagement receiving surface 2 of the lock plate 20
Of course, Oa and the first engaging surface 4c of the brake plate 4 are arranged to face each other. A cam 25 is inserted into the upper end of the upper sleeve 13 and is in contact with the cam nut 18, and is driven by an operating lever 26. Note that 27 in the figure is a mounting screw hole provided in the cylindrical portion of the lower sleeve. The caster with a braking device according to the present invention is constructed as described above, and its operation will be explained next. A rod-shaped casing consisting of an upper sleeve 13 and a lower sleeve 12 of this caster is a pipe P (indicated by a dotted line in Fig. 2) that serves as a support leg for a medical bed, etc.
The pipe P is fitted into the hollow part almost without any gaps until the lower end of the pipe P collides with the fixed base plate 8 or the auxiliary piece 8', and the mounting screw is tightened from the outside of the pipe P into the mounting screw hole 27. do. The assembly is then completed by attaching the operating lever 26 to the pipe P from outside. At this time, the rotating lock plate 2 inside the casing
If you want to adjust the neutral position of
The height of the upper sleeve 13 can be adjusted up and down by turning the screw 3 every half turn (180°). That is, by adjusting the height of the upper sleeve 13, when the upper sleeve 13 is lowered, the cam 25 is lowered by pressure, and when the upper sleeve is raised, the upward biasing force of the lock pin 15 that presses the cam 25 from below causes the cam 25 to lower. The cam 25 rises, and in conjunction with the vertical displacement of the cam 25, the lock pin 15 and the swing lock plate 20 fixed thereto move vertically. Thereby, it becomes possible to accurately set the neutral position of the swing lock plate 20, and it becomes possible to reliably perform braking, which will be described later. In the neutral position shown in FIG. 1, the cam 25 and the cam nut 18 are in contact with the first portion 25a of the cam 25, but the lock pin 15 is biased by the coil spring S and positioned at the top. There is. Therefore, the turning lock plate 20, the brake plate 4, the notch 20d of the turning lock plate 20,
Since the and claw portions 5a are spaced apart, the wheels can rotate freely and can also turn freely. Next, when the cam 25 is rotated via the operating lever 26 and the second portion 25b of the cam 25 comes into contact with the cam nut 18, the stroke of the cam 25 becomes slightly longer than in the above-mentioned neutral state. is slightly lowered against the coil spring S, and the notch 2 of the turning lock plate 20
0d and the claw portion 5a of the stopper 5 engage with each other. As a result, the turning of the turning base 1 to the wheels 2 is locked, and the notch 20d and the claw 5
By engagement with a, the wheels 2 can travel straight. Further, when the cam 25 is rotated via the operating lever 26 and the third portion 25c of the cam 25 comes into contact with the cam nut 18 as shown in FIG. 3, the stroke of the cam 25 becomes maximum. The lock pin 15 will be further lowered. the result,
The first engagement receiving surface 20a of the swing lock plate 20 and the first engagement surface 4c of the brake plate 4 come into contact with each other, and the brake plate 4 swings about the shaft 3 as a fulcrum.
Since the lower surface of the brake plate 4 comes into pressure contact with the outer circumferential surface of the wheel, rotation of the wheel 2 is locked, and at the same time, the rotation of the rotating platform 1 and the wheel 2 is also locked. Furthermore, the operating lever for driving the cam may be provided individually for each caster, but it may also be driven as a link mechanism that can be interlocked with a connecting bar provided between supporting legs of a medical bed or the like.

【Effect of the invention】

As described above, according to the caster with a braking device according to the present invention, since the height can be adjusted by rotating the upper sleeve, it is possible to finely adjust the position of the lock pin or rotating lock plate during installation. Therefore, engagement with the stopper can be achieved reliably. Although the provision of the threaded portion requires space in the radial direction of the casing, since the coil spring is housed in the spring insertion chamber, the gap can be narrowed and the casing can be prevented from becoming larger. Further, since a rotation prevention member is fixed to the lower sleeve of the casing and the legs are locked to the rotation lock plate, rotation can be prevented even if a round bar is used as the lock pin.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view showing the caster according to the present invention in a neutral state, FIG. 2 is a rear view of the same, FIG. The figure is a perspective view showing the relationship between the rotation preventing member and the swing lock plate used in the caster of the present invention, FIG. 5 is a sectional view showing the relationship between the swing lock plate and the stopper, and FIG.
FIG. 7 is a plan view showing the relationship between the swing lock plate and the stopper in the figure. FIG. 1...Support yoke, 2...Wheel, 3...Axle, 4
...Brake plate, 4c...First engagement surface, 5...Stopper, 5a...Claw portion, 7...Lower plate, 8...Upper plate, 11...Rotation prevention member, 12...Lower sleeve, 13...Top sleeve, 15...Lock pin,
17... Adjustment nut, 18... Cam nut, 20
...Swivel lock plate, 20a...First engagement receiving surface.

Claims (1)

[Claims] 1. A hollow cylindrical casing is fixed so that its lower end penetrates the fixed base plate 8 and protrudes downward, and a swivel base plate 1 is mounted below the fixed base plate 8 using a radial ball bearing. A support yoke 1' is connected to the rotating platform 1, and a wheel 2 is pivotally supported at the tip thereof, and an operating lever projecting outward is provided in the upper part of the hollow of the casing. A lock pin 15 having a built-in cam 25 that is rotatably displaced at 26 and biased upward so that its upper end contacts the cam 25 is provided so as to be able to slide up and down in the hollow of the casing. A rotating lock plate 20 is provided so as to be interlockable, and the lock pin 15 engages with a second engaging portion 5c of a stopper 5 provided on the rotating platform 1 in the halfway lowered position to lock the rotation of the rotating platform 1. The second engagement receiving portion 20d and the first engagement receiving portion 20a, which engages with the first engagement portion 4c of the brake plate 4 provided on the rotating platform 1 when the lock pin 15 is further lowered, are rotated. In a caster with a braking device, which is provided on a lock plate 20 and allows the bottom surface of the brake plate 4 to brake the wheel 2 by the thrust of a lock pin 15, the casing is vertically divided into an upper sleeve 13 and a lower sleeve 12; One of the lower ends of the sleeve 13 and the upper end of the lower sleeve 12 is fitted onto the other, and screws 13s and 12 are respectively inserted in the axial direction on the opposing surfaces.
A spring insertion chamber 12b is expanded along the inner wall of the lower sleeve 12 to have a larger diameter than the hollow part, and a coil spring S is housed therein. is fitted onto the lock pin 15,
Its upper end abuts against the protrusion 16 of the lock pin 15 to urge the lock pin 15 upward, and the rotating lock plate 20 is formed with an engaging recess 20c consisting of a recess or a hole that opens upward. The sleeve 12 is integrally provided with a rotation preventing member 11 having a leg portion 11a hanging therefrom, and the leg portion 1
A caster with a braking device, characterized in that 1a is slidably engaged with the engagement recess 20c. 2. The swing lock plate 20 has a disc shape, and a first engagement receiving portion 20a is formed in an annular shape along the circumferential direction on the bottom wall thereof, and a second engagement receiving portion 20a is formed in the outer wall in a radial direction. A receiving portion 20d is formed, and the brake plate 4 and the stopper 5 are coaxially pivoted to the rotating platform 1, and the stopper 5 is biased upward so that the position of the second engaging portion 5a is adjusted. , above the first engaging part 4c, the lock pin 15 enters the second engaging receiving part 20d at the halfway lowered position, and the first engaging receiving part 20a, in which the lock pin 15 has further lowered, is connected to the first engaging receiving part 20a of the brake plate 4.
At the position where it engages with the engagement portion 4c, the second engagement receiving portion 20
A caster with a braking device according to claim 1, wherein the caster is held in a position away from d.