JPH0675803U - Castor - Google Patents

Abstract

(57) [Summary] [Purpose] To prevent damage to the tip of the sled member and the stopper member when climbing over a step. [Structure] Thrust bearing 1 is attached to support shaft 11 of chassis 10.
The fork 13 rotatably supported via the wheel 14, the wheel 14, the sled member 17 whose center of gravity G is set in front of the pin 18 in the traveling direction of the wheel 14, and the upward movement of the sled member 17 on the rear end side. A second stopper member 24 for regulating is provided. The first stopper member 15 fixed to the support shaft 11 is provided with a groove 25 that can be engaged with the tip 19 of the sled member 17. [Effect] Since the upper limit is restricted by the second stopper 24 during traveling on a flat road surface, the sled member 17 is separated from the road surface 22. Lower surface 21 of sled member 17 when step 26 of caster gets over
When slides on the step 26, the tip 19 of the sled member 17 rises and is engaged with the groove 25 of the first stopper member 15. Sled 1
When the pin 18 of 7 passes through the step 26, the tip side of the sled member 17 is lowered by its own weight, and the engagement between the tip 19 and the groove 25 is released.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a caster, and more particularly, to a caster provided with a sled plate for overcoming a step on a road surface, for example, effective for use as a trolley.

[0002]

[Prior art]

 Conventionally, as a caster used for a dolly or the like, the one described in JP-A-64-44301 is known. This caster is supported by a support shaft vertically fixed to the lower surface of the chassis, a fork rotatably supported at the lower end of the support shaft about the support shaft, and a position separated from the extension line of the support shaft. A support shaft arranged in a direction orthogonal to the shaft and fixed to the fork, a wheel rotatably supported on the support shaft, and a swingably connected to the fork and extended forward in the traveling direction of the wheel. The sled member is provided with a stopper member that is fixed to the support shaft and that controls the upward movement of the sled member tip by engaging with the tip of the sled member. A warped portion is formed between the sled plate and the tip of the sled plate so as to warp forward in the traveling direction of the wheel, and the stopper member is formed with an engagement portion that is engageable with the tip of the sled member.

According to this caster, when there is a step on the road surface, the front of the sled member first rides on the step, and then the lower surface of the sled member moves as the rear wheel moves. Slips up a step, and along with this, the trolley is moved forward while the wheels are lifted. In this case, since the tip of the sled member and the stopper member are engaged with each other, the fork is automatically prevented from being bent in a direction different from the forward direction of the wheel.

[0004]

[Problems to be solved by the device]

 In the casters described above, the sled member support points and the wheel support points are set at the same location, and these support points are located behind the sled members, so the sled members move away from the step. Up to this point, a force that pushes the sled member tip upwards works, and the sled member tip engages with the groove of the stopper. Therefore, it takes time for the leading end of the sled member to switch from the engaged state with the groove of the stopper to the disengaged state. Moreover, at this time, the engagement between the tip of the sled member and the groove of the stopper becomes a semi-engaged state, so if the engagement between the tip of the sled member and the groove is misaligned, the stopper will be damaged. I'm afraid.

An object of the present invention is to provide a caster capable of preventing the tip of the sled member and the stopper from being damaged.

[0006]

[Means for Solving the Problems]

 The caster according to the present invention comprises a support shaft vertically fixed to a chassis, a fork rotatably supported by the support shaft around the support shaft, and a support shaft at a position deviated from an extension line of the support shaft. A support shaft arranged in a direction orthogonal to and fixed to the fork, a wheel rotatably supported by the support shaft, and a swingably connected to the fork and extended to the front in the traveling direction of the wheel. The sled member is fixed to the fork and the rear end of the sled member is abutted against the first stopper member that is fixed to the support shaft and restricts the upward movement of the sled member tip by engaging the sled member. A second stopper member that restricts the upward movement of the rear end of the member is provided, and the sled member is warped forward between the connection point with the fork and the tip of the sled member in the traveling direction of the vehicle wheel. The warped portion is formed, and the first stopper member has a sled member. In a caster having an engaging portion that can be engaged with an end, the sled member is connected to the fork in the vicinity of the extension line of the support shaft, and the center of gravity of the sled member advances from the connection point with the fork of the wheel. The feature is that it is set forward in the direction.

[0007]

[Action]

 According to the above-described means, when traveling on a road surface without steps, the wheels are allowed to move on the road surface while the rear end of the sled member and the second stopper member are prevented from hanging down. It will run while rolling.

On the other hand, when there is a step on the road surface, first, the tip portion of the sled climbs up the step, so the sled swings forward and upward around the connection point with the fork, and the sled moves. The tip of the material is engaged with the engaging portion of the first stopper member. This engagement prevents the caster from being bent in the traveling direction. In this state, when the casters are moved further forward, the lower surface of the sled member slides over the step and gets over.

Then, when the sled member gets over the step and the connection point between the sled member and the fork passes the position of the step, the center of gravity of the sled member is set forward of the connection point with the fork in the traveling direction of the wheels. Therefore, gravity acts on the sled member in the direction in which the tip of the sled member descends. Moreover, the end of the step acts on the rear part of the connection point of the sled member, and a moment acts in the direction in which the tip is lowered. Therefore, the engagement between the tip of the sled member and the engaging portion of the first stopper member is released. Therefore, the time required for the engagement state between the tip of the sled member and the engagement portion of the first stopper member to shift to the disengaged state is shortened. Therefore, it is less likely that the front end of the sled member and the engaging portion of the first stopper member will be in a semi-engaged state, so that the front end of the sled member and the stopper member are prevented from being damaged. You can

[0010]

【Example】

 FIG. 1 shows a caster according to an embodiment of the present invention, in which (a) is a side view and (b) is a partially cut front view.

In the present embodiment, the caster according to the present invention is used for a dolly, and is arranged at the bottom of the chassis 10 that constitutes the dolly body. The dolly is provided with drive wheels (not shown), and the drive wheels are arranged at the rear part of the dolly chassis 10. A pair of support shafts 11 (only one of which is shown) for supporting the front wheels are provided at the front side position on the bottom of the chassis 10 and are arranged on the left and right and fixed vertically downward. Wheels 14 for front wheels are connected to the bottom of each support shaft 11 via thrust (thrust) bearings 12 and forks 13.

At the lower end of the support shaft 11, a first stopper member 15 and a thrust bearing 12 are axially arranged in order from the top and fixed. A fork 13 is rotatably fixed to the lower surface of the thrust bearing 12 with the support shaft 11 as the center of rotation. At the rear of the extension line of the support shaft 11 in the fork 13, a rotary shaft 16 is installed so as to extend in a direction perpendicular to the support shaft 11, and a wheel 14 is rotatably mounted on the rotary shaft 16. It is pivotally supported.

Further, a sled member 17 is swingably connected to the fork 13 on an extension line of the support shaft 11 via a pin 18. The sled member 17 is vertically swingably connected to the fork 13 by using the pin 18 as a connection point with the fork 13. The sled member 17 is connected to the fork 13 of the wheel 14 between the pin 18 and the tip 19 of the sled member 17. A warped portion 20 is formed so as to warp forward in the traveling direction.

The sled member 17 is set such that its center of gravity G is located in front of the pin 18 in the traveling direction of the wheel 14. Therefore, in a normal traveling state, the tip 19 of the sled member 17 is in a hanging state. In this embodiment, in order to prevent the lower surface 21 of the sled member 17 from coming into contact with the road surface 22 due to the hanging down of the tip 19 of the sled member 17 during normal traveling, the sled member 17 is abutted against the upper surface 23 of the sled member 17. A second stopper member 24 that restricts the upward movement of the material 17 is fixed to the fork 13. Therefore, during normal traveling, the sled members 17 are arranged at a constant distance from the road surface 22.

Further, the tip 19 of the sled member 17 is arranged in the vicinity of the first stopper member 15, and the tip 19 of the sled member 17 is formed in a triangular shape that is pointed upward. The tip 19 of the sled member 17 is formed so as to be engageable with the triangular engaging groove 25 formed in the first stopper member 15.

Next, the operation will be described. When the caster according to the above configuration travels on the flat road surface 22 without the step 26, the tip 19 of the sled member 17 is separated from the groove 25 of the first stopper 15, and the upper surface 23 of the sled member 17 is moved to the first position. The second stopper member 24 is in contact with the stopper member 24. As a result, the casters travel as the wheels 14 roll with the sled member 17 maintaining a constant distance from the road surface 22.

On the other hand, when the caster climbs over the step 26 existing on the road surface 22, first, the tip end side of the sled member 17 located on the front side in the traveling direction rides on the step 26. When the lower surface 21 of the sled member 17 rides on the step 26, the front side of the sled member 17 swings upward with the pin 18 as a fulcrum, so that the tip end 19 of the sled member 17 is engaged with the groove 25. When the tip end 19 of the sled member 17 is engaged with the groove 25, the traveling direction of the caster is prevented from being unexpectedly bent. Therefore, the carriage can maintain the desired traveling direction.

In this state, when the caster is moved further forward, the caster is advanced so that the lower surface 21 of the sled member 17 slides on the step 26. When the position of the pin 18 is in front of the step 26, the center of gravity G of the sled member 17 is set in front of the pin 18, so that the gravity in the direction in which the front of the sled member 17 hangs down. Act on. Due to this gravity, the sled member 17 automatically swings forward and downward. Further, when the rear portion of the sled member 17 beyond the pin 18 passes over the step 26, a moment in the counterclockwise direction is generated around the pin 18 in the sled member 17 as shown in FIG. Due to these effects, the tip 19 of the sled member 17 is automatically and quickly separated from the groove 25, and the engagement between the tip 19 of the sled member 17 and the groove 25 is automatically and quickly released.

When the caster moves further forward, the wheels 14 get over the step 26, and thereafter, the caster is moved on the road surface 22 by the same action as the above-described flatland traveling.

As described above, according to the present embodiment, when the caster gets over the step 26, the state in which the tip end 19 of the sled member 17 is engaged with the groove 25 is changed to the disengaged state. Since the time can be shortened, the time during which the tip 19 of the sled member 17 and the groove 25 are in a semi-engaged state can be shortened, and the tip 19 of the sled member 17 and the groove of the first stopper 15 can be shortened. 25 can be prevented from being damaged.

As shown in FIG. 1A, a leaf spring 27 is provided on the fork 13, and the thrust spring 12 is pressed by the leaf spring 27, or the leaf spring 28 is attached to the thrust bearing 12. If the plate spring 28 is provided and the sliding surface 29 of the fork 13 is pressed, the frictional force between the fork 13 and the thrust bearing 12 increases, so that excessive turning motion of the caster is restricted. be able to.

[Effect of device]

 As described above, according to the present invention, since the center of gravity of the sled member is set to the front side in the traveling direction of the wheels rather than the connection point with the fork, when the caster rides on the step, the first The time during which the stopper member and the tip of the sled member are in the disengaged state can be shortened, and damage to the sled member and the stopper member can be suppressed.

[Brief description of drawings]

FIG. 1 shows a caster according to an embodiment of the present invention, (a) is a side view and (b) is a partially cut front view.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... Bogie chassis, 11 ... Support shaft, 12 ... Thrust bearing, 13 ... Fork, 14 ... Wheel, 15 ... 1st stopper member, 16 ... Spindle, 17 ... Sled material, 18 ... Pin (connection point), 19 ... Sled material tip, 20 ... Warped portion, 21 ...
Lower surface, 22 ... Road surface, 23 ... Upper surface, 24 ... Second stopper member, 25 ... Groove, 26 ... Step, 27, 28 ... Leaf spring, 29
… Sliding surface.

Claims (1)

[Scope of utility model registration request] 1. A support shaft vertically fixed to a chassis, a fork rotatably supported by the support shaft about the support shaft as a rotation center, and a position orthogonal to the support shaft at a position deviated from an extension line of the support shaft. A support shaft fixed in the fork and fixed to the fork, a wheel rotatably supported by the support shaft, and a sled member that is swingably connected to the fork and extends forward of the wheel in the traveling direction, The first stopper member, which is fixed to the support shaft and restricts the upward movement of the sled member tip by engaging with the tip of the sled member, and the fixed end of the sled member, which is fixed to the fork, rises the rear end of the sled member. A second stopper member for restricting movement of the sled member, wherein the sled member is provided with a warped portion that is warped forward toward the front in the traveling direction of the wheel between the connection point with the fork and the tip of the sled member. The first stopper member is engaged with the sled member tip. In the caster in which a joint portion is formed, the sled member is connected to the fork in the vicinity of the extension line of the support shaft, and the center of gravity of the sled member is set forward in the traveling direction of the wheels from the connection point with the fork. Casters characterized by being present.