JPH0455210A - Braking device - Google Patents

Abstract

PURPOSE:To improve the accuracy of a stop position in a braking device for a belt conveyor by fitting a cam to a rotating shaft to be braked, and bringing a roller into contact with the cam by an air cylinder to perform braking. CONSTITUTION:A roller 4 is normally positioned outside the rotational locus 3a of the apex 10a of a cam 3 so as to be placed in its receding position. At the time of braking, however, an air cylinder 7 is operated at a place surpassing the apex 10a so as to push the roller 4 out so as to be in contact with the cam 3. The roller 4 is thereby rotated in contact with the induction face 10c of the rotated cam 3, and drive source is cut off at the time of surpassing the bottom part 10b of the cam 3. The cam 3 is then placed into inertial rotation, and the roller 4 is brought into contact with a control face 10d so as to push the air cylinder back against cylinder pressing force. This push-back action becomes braking action to stop the cam 3, and a braked shaft 2 is stopped.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a braking device, for example, a braking device for correctly stopping an article at a predetermined position when the article is transferred by a belt conveyor.

[Conventional technology]

FIG. 6 shows the procedure for transporting articles by the belt conveyor. A driven sprocket wheel 53 is provided on a drive shaft 52 to which a drive pulley 51 for winding a conveyor belt 50 is attached, and a chain wheel 56 is passed between the driven sprocket wheel 53 and a driving sprocket wheel 55 attached to a motor 54. 57 is a tension gear for absorbing the slack of the chino 56. The motor 54 uses a motor with a brake, and the conveyor belt 5
0'', the conveyed article W is placed in the direction of the arrow, and when the conveyed article W reaches a predetermined position, the motor 54 is stopped and the brake is applied.

However, in this case, due to the inertia of the conveyed object W, the drive pulley 5
1 over-rotates, the chain 56 is bent as shown by the dotted line 56a, and is pulled in the opposite direction by the action of the tension gear 57, and the drive pulley 51 rotates in the opposite direction and stops. However, the repulsive force generated by the tension gear 57 is generally weak, and therefore the stopping position of the conveyed object W is not constant.

As a means for stopping at a predetermined position, which is generally used as a solution to this problem, a pulley (or disc) is attached to the drive shaft 52, that is, a shaft to be braked, and a brake shoe is placed opposite the brake shoe. ) A friction brake system that stops by pressing against the ground.The cylinder (or disk) that forms the ground is equipped with a pawl that engages with the surface that faces the lees, and one cylinder (or disk) is attached to the above-mentioned braked shaft, and both pawls are There is a method using a dog clutch that engages the brake shaft to stop the rotation of the braked shaft.

Still another method is to use the Geneva system, in which a driven gear with equally spaced pin grooves in the radial direction is attached to the shaft to be braked, and a driving wheel that protrudes in the radial direction to fit into the pin grooves is rotated. There is a method in which the rotation of the shaft to be braked is stopped intermittently and at predetermined angle intervals.

Other than that, methods using electromagnetic brakes or air brakes have also been attempted.

[Problem to be solved by the invention]

The above-mentioned method using a friction brake has problems such as the stopping position of an article conveyed by a conveyor or the like is not constant due to inertia force, friction of brake shoes, etc.

Furthermore, when using the dog clutch method, the pitch of the pawls must be quite long in order to provide strength to the pawls. Follower/
There is a curved head of a rod that does not stop at a predetermined position due to misalignment of one pawl.

In addition, the engagement may cause a sudden braking stop, damage the equipment, or cause objects on the conveyor belt to move due to inertia.
There are problems such as not stopping at a predetermined position.

In addition, in the Geneva method, the rotation angle of the braked shaft is constant,
It is difficult to change it freely.

Furthermore, since the electromagnetic braking method, that is, braking by electromagnetic force, involves sudden braking, a large inertial force is applied before and after the brake, which may damage the device and has the disadvantage that the conveyed object moves due to the inertial force.

In view of this, an object of the present invention is to accurately stop the vehicle at a predetermined position by absorbing the inertial force during braking.

[Means to solve the problem]

The gist of the braking device of the present invention for achieving the above object is as follows. A cam attached to a rotating shaft to be braked,
A roller is provided opposite to the cam, and this roller is moved forward relative to the cam by an air cylinder and engages with the cam surface to stop rotation of the braked shaft.

The cam surface is connected to the bottom of the smallest diameter part and consists of a guide surface that allows the roller to enter as the cam rotates, and a braking surface that is formed beyond the bottom.The braking surface connects the roller to the air cylinder. It is preferable to push out against the pressing force of , and to prevent inertial rotation of the braked shaft.

Furthermore, the air cylinder preferably includes supply pressure air adjustment means for adjusting the roller extrusion pressure.

Furthermore, it is preferable that the air cylinder includes a synchronizing means that operates when the roller faces a predetermined surface of the cam in synchronization with the rotation of the cam.

[For production]

During braking, the roller is pushed out by the air cylinder and comes into contact with the cam. The cam rotates together with the braked shaft, and rotation is prevented by the roller coming into contact with the bottom of the cam.

In this case, the cam surface is provided with a roller guide surface and a braking surface with the bottom of the minimum diameter interposed therebetween, so that the roller passes the bottom and reaches the braking surface. This braking surface pushes the roller back against the pressing force of the air cylinder, and this action causes the cam, that is, the braked shaft, to be stopped in a buffering manner.

Further, when the air cylinder is provided with a supply pressure air adjusting means, the angle of the cushioning rotation can be arbitrarily adjusted.

Further, when a synchronizing means is provided to synchronize the operation of the air cylinder with the rotation of the cam, the roller can be pushed out when the roller is opposed to the most suitable position of the cam.

〔Example〕

The figure shows an embodiment of the invention. The braking device 1 includes a braked shaft 2
The roller 4 includes a cam 3 attached to the cam 3 and a roller 4 provided opposite to the cam 3. The roller 4 is attached to the tip of an arm 6 whose one end is supported by a support shaft 5, and an air cylinder 7 is connected to the arm 6 at a suitable position.

The cam 3 has a plurality of cam surfaces 10, for example three, formed on its outer periphery. As shown in FIG. 3, the cam surface 10
A guiding surface 10c connecting the apex 10a of the cam and the bottom portion 10b of the minimum radius to receive the entry of the roller 4 when the cam rotates in the direction, and a braking surface lO formed beyond the bottom portion lOb.
It consists of d.

The braking surface 10d is, for example, a straight line, and the angle θ with respect to the radius is appropriately selected. As will be described later, this angle θ is used to buffer the inertial rotation of the driven shaft 2, and the size of this angle θ is determined experimentally. Alternatively, as shown by the chain line 10e, it is formed into a curved surface that is gentle at first and then gradually slopes.

In FIG. 1, 11 is a driven sprocket wheel attached to the hollow shaft 12 of the cam 3, and 13 is this hollow shaft 1.
2 to the braked shaft 2. The locking member 13 allows rotation of the hollow shaft 12 by loosening the locking member 13, and is fixed to the braked shaft 2 by rotating the cam 3 to an arbitrary position and fastening the locking member 13. 1
Reference numeral 4 denotes a mounting frame, which passes through the driven shaft 2 and is rotatably supported by a bearing 15. , 16 is the drive sprocket wheel, 17 is the chino not shown.

Reference numeral 21 denotes a supply pressure air adjustment means provided in the pressure air supply circuit 20 of the air cylinder 7, which is provided to control the pressure on the air cylinder side, and is composed of a pressure reducing valve or the like. Reference numeral 22 denotes an on-off valve, which is normally closed, for example, and opens during braking to supply pressurized air to the air cylinder 7. It is preferable that the air cylinder 7 is operated when the roller 4 faces the guiding surface], Oc. Therefore, for example, the on-off valve 22 is an electromagnetic on-off valve, and the position of the cam is electrically detected and the on-off valve is activated. Tuning means 25 are provided for operating the .

Next, the operation procedure will be explained based on FIG.

As shown in FIG. 3A, the roller 4 is normally held at a retracted position outside the rotational trajectory 3a of the apex 10a of the cam 3. ] At a point beyond Oa, actuate the air cylinder 7 to push out the roller 4 and bring it into contact with the cam 3. That is, when the roller 4 faces the guiding surface [Oc] of the cam surface 10, the on-off valve 22 is opened and the air cylinder 7 is operated. As a result, the roller rotates in contact with the guiding surface IOC of the rotating cam, as shown in FIGS. (Due to the contact surface, the braking force does not work yet) and (e) the bottom 10 shown in the figure.
Turn off the drive source at a point beyond b. At this point, the cam 3 enters into inertial rotation. The roller 4 is in contact with the control surface 10d (f) in the same figure.
, is pushed back against the pressing force of the air cylinder 7. (
(The contact angle increases) At the same time, this action becomes a braking action, and the cam 3 finally stops.

During the angle α (see FIG. 3) between passing the bottom portion 10b and stopping, there is a buffer movement during braking, and the braking force gradually becomes stronger. This angle α is related to the pressing force of the air cylinder 7, that is, the supplied air pressure, as well as the angle θ or the shape of the braking surface 10d. However, it is difficult to adjust the angle θ, etc. during use, and therefore the supply pressure air adjustment means 21 is used to adjust the angle θ.

Thereby, the angle α is appropriately selected depending on the magnitude of the inertial force applied to the braked shaft 2, and the predetermined stopping position is maintained constant by adjusting the air pressure to the air cylinder 7 by the supply pressure air adjusting means 21.

FIG. 5 shows an example in which the present invention is applied to a belt conveyor.

The drive pulley 31 around which the conveyor belt 30 is wound is attached to the braked shaft 2 described above. The rest of the structure is the same as described above.

In this case, when the conveyed object W approaches a predetermined stop position, the inertial force is absorbed and the object W is accurately stopped at the predetermined position.

〔Effect of the invention〕

According to the present invention, a cam is attached to the shaft to be braked, and during braking, the roller is pressed against the cam by an air cylinder and engaged with the cam surface, so that braking can be performed reliably.

At this time, the cam surface is designed to prevent the roller from entering as the cam rotates.
When the roller is configured with a guiding surface that pushes the roller against the pressure of the air cylinder, and a braking surface that pushes out the roller against the pressure of the air cylinder, the inertial rotation due to the inertial force of the cam pushes the roller by the braking surface, and the air cylinder acts as a shock absorber. Therefore, the braked shaft will stop after the inertial force is absorbed. Therefore, when this device is applied to a belt conveyor, the conveyed object does not shift its stopping position due to inertial force.

Therefore, when a supply pressure air adjustment means is provided, it is effective for finely adjusting the stop position.

Furthermore, when a synchronizing means is provided to synchronize the timing of the roller extrusion by the air cylinder with the rotation of the cam, it is effective to prevent the extruded roller from immediately coming into contact with the braking surface, thereby preventing malfunction.

[Brief explanation of the drawing]

1 to 5 relate to a basic embodiment of the present invention, in which FIG. 1 is a front view of the braking device, FIG. 2 is a sectional view taken along line I-1 in FIG. 1, and FIG. 3 is a cam surface view. Detailed explanatory diagram, Figure 4 is made.
FIG. 5 is an explanatory diagram in which the braking device of the present invention is applied to a belt conveyor, and FIG. 6 is an explanatory diagram of conventional braking procedures. 1 is a braking device, 2 is a braked shaft, 3 is a cam, 4 is a roller,
7 is an air cylinder, 10 is a cam surface, 10b is a bottom part, 10
10d is a braking surface, 21 is a supply pressure air adjusting means, and 25 is a tuning means. In addition, the pressure air adjustment area for the air cylinder is shown in Fig. 5\Fig. 6 Procedural amendment (voluntary) 1゜Representation of the case Patent application No. 2]6], 019 2゜Name of the invention Braking device 3゜Claims Number 4゜Relationship with the case of the person making the amendment

Claims (4)

[Claims] (1) Equipped with a cam attached to the rotating shaft to be braked and a roller installed opposite to this cam, this roller is advanced relative to the cam by an air cylinder and engages with the cam surface to stop the rotation of the shaft to be braked. A braking device characterized by: (2) The cam surface is continuous with the bottom of the smallest diameter part and consists of a guiding surface that allows the roller to enter as the cam rotates, and a braking surface that is formed beyond the bottom. 2. The braking device according to claim 1, wherein the braking device pushes out against the pressing force of the cylinder to prevent inertial rotation of the shaft to be braked. (3) Claim 1 or 2, wherein the air cylinder is equipped with supply pressure air adjustment means for adjusting the roller extrusion pressure.
Braking device as described. (4) The braking device according to claim 1 or 2, wherein the air cylinder is provided with a synchronizing means that operates when the roller faces a predetermined surface of the cam in synchronization with the rotation of the cam.