JPH0715573Y2 - Pitching mechanism of baseball practice pitcher - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial application field) The present invention relates to a pitching mechanism of a so-called arm-type baseball practice pitching machine.

(Prior Art) Some of the above-described arm-type baseball pitchers for baseball practice are conventionally configured as follows.

That is, a rotating shaft having a horizontal axis is supported by a mount placed on the ground. An arm is provided so as to project from the rotary shaft, and a ball receiving portion for mounting a ball for pitching is provided at a protruding end of the arm. Further, spring means is provided for urging the arm in one direction via the rotary shaft within a partial angular range of the entire circumference around the rotary shaft.

Then, when the arm is momentarily rotated at a high speed by the biasing force of the spring means, the ball on the ball receiving portion of the arm is thrown toward the target by the centrifugal force.

On the other hand, after the pitching, the arm reaches the end of the angular range biased by the spring means, and beyond this, the biasing force of the spring means thereafter acts on the arm in the opposite manner. Try to rotate the arm in the opposite direction. For this reason, the shocking vibration of alternating forward and reverse rotation tends to occur in this arm.

Therefore, in order to prevent this, a braking device for braking the arm via the rotary shaft is provided. This braking device is composed of a braked body mounted on a rotating shaft and a braked body mounted on the pedestal side so as to correspond to the braked body, and the end of the angular range in which the arm is biased by spring means. When the force reaches, the braked body is frictionally joined to the braked body to brake the rotation of the arm while counteracting the bias of the spring means.

Further, in this case, in the conventional case, the body to be braked is composed of a drum, and the drum is eccentrically attached to the shaft center of the rotating shaft, and the protruding portion on the outer peripheral surface of the drum is braked when viewed from the shaft center of the rotating shaft. It is designed to be friction bonded to the body.

(Problems to be Solved by the Invention) In the above-described conventional configuration, the braking body is fixedly provided on the frame via the position adjusting screw, and therefore has the following problems.

That is, first, when the braked body is frictionally joined to the brake body and the joining surfaces of these members are consumed even a little, the frictional joining force is suddenly reduced, and desired braking cannot be obtained. Therefore, according to the consumption, the position adjusting screw is operated to adjust the braking body to an appropriate position with respect to the body to be braked, and work for maintaining the frictional joining force at a predetermined value is performed.

However, such an operation needs to be performed in a relatively short period of time depending on the degree of wear, which is extremely complicated.

Secondly, an impact force is generated when the braked body that rotates along with the rotating shaft collides with the braked body in an attempt to start frictional bonding to the braked body. Will be consumed more heavily.

Further, although the braked body is composed of a drum as described above, such a drum is heavy. Therefore, the inertial force when the braked body rotates along with the rotating shaft increases, and in order to obtain a desired braking force,
It is necessary to increase the frictional joining force of the braked body with respect to the brake body, and thus the wear of the joint surface between the braked body and the brake body becomes more severe.

Further, since the joint surface is consumed so much in this manner, there is a problem that the life of the braking device is shortened.

(Purpose of Invention) This invention was made in view of the above circumstances, and facilitates the work for keeping the friction matching force of the braked body at a predetermined value with respect to the brake body. In addition, the object is to extend the life of the braking device.

(Structure of the Invention) A feature of the present invention for achieving the above-mentioned object is that a braked body is attached to a rotary shaft having an arm projecting, and a brake body is mounted on a pedestal side so as to correspond to the braked body. In the case where the braked body is frictionally bonded to the braking body when the arm reaches the end of the angular range by being attached by the spring means, the braked body is frictionally bonded to the braking body. The braking body is brought into pressure contact with the braked body by the elastic force of the spring, and the braked body is provided with an arm protruding from the rotating shaft and the outer peripheral surface of the arm provided at the protruding end of the arm is frictionally joined to the braking body. It is constituted by an arcuately viewed side portion and a braked portion, and the braked portion is formed so as to gradually approach the rotation axis as it goes forward in the rotation direction of the braked portion.

(Operation) The operation of the above configuration is as follows.

When the braked body 59 is frictionally joined to the brake body 64,
Since the elastic force of the spring 64 presses the braked body 59 against the braked body 59, even if the joint surfaces of the braked body 59 and the brake body 64 are worn to some extent, the above-mentioned elastic force causes the braked body 59 against the braked body 64. The frictional joining force is maintained at a predetermined value.

Further, the braked body 59 that rotates with the rotating shaft 30 is
When the body 59 to be braked collides with the braking body 64 in an attempt to frictionally bond to the, a shock force is generated, which is absorbed by the spring 71.

In addition, the braked body 59 and the arm 62 protruding from the rotating shaft 30,
The outer peripheral surface of the arm 62 is provided on the protruding end of the arm 62.
And a braked portion 63, which has an arcuate shape in a side view and is frictionally joined to.

For this reason, conventionally, the braked body 59 is composed of a drum, and there are many useless portions that do not contribute to frictional joining with the brake body 64, but according to the braked body 59, Such useless parts are deleted.

Further, the braked portion 63 is formed so as to gradually approach the rotary shaft 30 as it goes forward in the rotation direction of the braked portion 63.

Therefore, as the braked body 59 rotates,
When the frictional joining to the
Since the pressure contact force of the braked portion 63 gradually increases, this joining is performed smoothly.

Therefore, as described above, the braked portion 63 is provided at the projecting end of the arm 62 and is different from the conventional drum type in the rotary shaft 30.
Although it exists only in a part of the circumferential direction, the impact force when the braked portion 63 collides with the braking body 64 can be suppressed to be small.

(Embodiment) An embodiment of the present invention will be described below with reference to the drawings.

1 and 2, reference numeral 1 is a pitcher for baseball practice, and an arrow Fr in FIG. 2 indicates the front of the ball 2 in the pitching direction. Hereinafter, for convenience of explanation, this pitching direction will be referred to as the front, and the left-right direction will be the direction toward this front.

The pitcher 1 has a dolly 4 placed on the ground 3, a pedestal 6 mounted on the dolly 4, a pitcher main body 7 supported by the pedestal 6 for pitching the ball 2, and a pitcher main body 7
The ball feeder 8 sequentially supplies the balls 2 to be thrown one by one.

The dolly 4 has a body frame 10, and four wheels 11 are attached to the body frame 10 so that it can move to a desired position on the ground 3. Further, the body frame 10 is provided with four screw jacks 12, and each screw jack 12 is mounted on the carriage 4
Equipped with axially oriented screws 13 screwed on each corner of
A round handle 14 is attached to the upper ends of these screws 13, and a grounding portion 15 is attached to the lower ends.

When the ground contact portion 15 is located above the ground 3 as shown by the phantom line in FIG. 1 and the solid line in FIG. 2, the carriage 4 can move freely. On the other hand, when the circular handle 14 is rotated to lower the screw 13 as shown by the phantom line in FIG. 2 to bring the grounding portion 15 into pressure contact with the ground surface 3, each wheel 11 separates from the ground surface 3 or to the ground surface 3. The press-contact force of is weakened and the dolly 4 is fixed on the ground 3, and the ball can be thrown.

The pedestal 6 has its front lower end pivotally supported by a pair of left and right pivot shafts 17, 17 so as to be vertically rotatable. An angle adjusting device 18 for adjusting the rotation angle of the pedestal 6 around the pivot shafts 17, 17 to a desired angle is provided.

The angle adjusting device 18 has a pivot shaft at the rear end of the body frame 10 of the bogie 4.
It has a support arm 20 pivotally supported by 19 so as to be rotatable back and forth, and a bolt body 21 is screwed to the pivot end of the support arm 20. A support piece 23 is provided in the upper and lower middle portions of the bolt body 21.
Is welded and the nut 24
Is screwed, and the rotating end 6a of the gantry 6 is fitted to the bolt body 21 between the support piece 23 and the nut 24.

A lower spring 25 is externally fitted to the bolt body 21 between the support piece 23 and the rotation end 6a of the pedestal 6, and the bolt body is the same as the bolt 24 between the nut 24 and the rotation end 6a of the pedestal 6. An upper spring 26 is externally fitted on 21. That is, the rotating end 6a side of the gantry 6 is supported by the support arm 20 via the support piece 23 and the bolt body 21 while being elastically sandwiched by the lower spring 25 and the upper spring 26.

A handle 28 is welded to the bolt body 21, and by operating the handle 28 and screwing the bolt body 21, the height of the bolt body 21 can be freely adjusted, that is, the angle of the pedestal 6 can be adjusted. You can do it. In addition, the nut 24
When the screw is operated, the elastic force of each spring 25, 26 can be adjusted, and the angle of the pedestal 6 can also be adjusted by this.

The pitcher body 7 is supported on the pedestal 6.
The pitcher main body 7 has a rotary shaft 30 extending horizontally in the left-right direction on the upper surface of the front part of the gantry 6, and the rotary shaft 30 has a pair of left and right bearings.
Both ends are supported on the base 6 by 31,31. A pitching arm 33 is attached to the right side of the rotary shaft 30. The throwing arm 33 is a boss portion screwed to the rotary shaft 30.
34, an arm body 35 screwed to the boss portion 34,
It is configured with a ball receiving portion 36 having a U-shaped cross section provided at the rotating end of the arm body 35.

Drive means 38 for rotating the throwing arm 33 in one direction
Is provided. The drive means 38 has an electric motor 39 attached to the pedestal 6. In addition, an electric motor is mounted on the base 6 as above.
A speed reducer 40 is attached above 39. The speed reducer 40 receives power from the electric motor 39 by the V belt transmission means 41. A drive chain wheel 43 is provided on the output side of the speed reducer 40, while a driven chain wheel 44 is provided on the rotating shaft 30 via a one-way clutch,
The driven chain wheel 44 is rotationally driven by the drive chain wheel 43 via the chain 45.

When the electric motor 39 is driven, the V-belt transmission means 41, the speed reducer 40, the drive chain wheel 43, the chain 45, and the driven chain wheel 4
4, and the rotating shaft 3 through the one-way clutch described above
0 is rotated in the direction of arrow A in FIGS. 1 and 2.

The arm 32 is rotated within a partial angular range of the entire circumference around the rotary shaft 30, that is, within a range of about 180 ° from the position of the arm 32 shown by the chain double-dashed line in FIG. 2 to the position shown by the solid line. Spring means for biasing in the direction of arrow A through the shaft 30
47 are provided.

Each end of the rotary shaft 30 is a free end protruding from the bearing 31 to the left and right, and a support arm 48 is attached to each free end, and each support arm 48 is attached.
Revolving arms 49 are pivotally supported by pivot shafts 50 at their respective protruding ends.

On the other hand, a supporting piece 51 is projectingly provided on each of the lower front portions of the pedestal 6, and each of the supporting pieces 51 has a screw 52 extending in the longitudinal axis direction.
Is attached so that it can slide up and down. A round handle 53 is attached to the lower end of this screw 52, and a nut 54 is attached to the upper end.
Is screwed on. The nut 54 is engaged with a restriction shaft 55 protruding from the support piece 51 and is restricted from rotating together with the screw 52. A pair of front and rear springs 5 are provided between the rotating end of each rotating arm 49 and each nut 54.
6,56 are erected in tension. As a result, the arm 32 is arranged between the left and right springs 56, 56.

If you rotate the screw 52 by operating the round handle 53,
The nut 54 moves up and down, whereby the tension of each spring 56 is variable.

In the above case, all springs 56 have the same shape and size, are parallel to each other, and generate the same biasing force.

In FIGS. 1, 3, and 4, reference numeral 58 denotes a braking device, which has a braked body 59 attached to the rotating shaft 30 and rotating together with the rotating shaft 30. The braking body 59 is arranged between the left and right springs 56, 56.

The braked body 59 is fitted onto the rotary shaft 30 by a bolt 60.
A boss 61 screwed by the boss 61, an arm 62 protruding from the boss 61, and a braked portion 63 welded to a protruding end of the arm 62. The braked portion 63 is formed of a wear-resistant metal plate, the braked portion 63 has a circular arc shape in a side view, and the outer peripheral surface thereof is a circular arc convex surface 63a having the axis of the rotary shaft 30 as its center. ing.

On the other hand, the pedestal 6 is provided with a braking body 64 for frictionally joining the braked body 59. This braking body 64 is a support base 65
The support base 65 is screwed to the base 6 with bolts 66. This support base 65 has a cylindrical body 67 with a longitudinal axis.
Are welded, and a screw 68 is vertically slidably fitted in the cylindrical body 67. A support piece 70 that detachably supports the friction material 69 is attached to the upper end of the screw 68, and the upper surfaces of the friction material 69 and the support piece 70 are arcuate concave surfaces with the axis of the rotating shaft 30 as the center. There is. Further, a spring 71 for urging the support piece 70 together with the screw 68 upward is provided. Furthermore,
A pair of lock nuts 72, 72 are screwed to the lower end of the screw 68.

Further, a rotation stopping means 73 for preventing the screw 68 from rotating around its axis is provided. The rotation stopping means 73 has a long groove 73a formed along the axial direction of the screw 68,
The bolt 73b is screwed to the cylindrical body 67 and slidably fitted in the long groove 73a. Then, as indicated by the phantom lines in FIGS. 3 and 4, the lock nuts 72, 7 are
The abutment of 2 with the lower end of the cylindrical body 67 prevents the screw 68 from further rising.

When the braked body 59 rotates along with the rotary shaft 30 and the braked portion 63 of the braked body 59 corresponds to the friction material 69 of the brake body 64, as shown by the solid lines in FIGS. 3 and 4. The part to be braked 63
The circular arc convex surface 63a is pressed against the friction material 69 by the elastic force of the spring 71, and the frictional bonding at this time brakes the rotation of the rotary shaft 30. At this time, the spring 71 absorbs the impact force when the braked body 59 collides with the braked body 64 when the braked body 59 starts to frictionally bond to the braked body 64.

In FIGS. 1 and 2, the ball feeder 8 includes an arm 32.
Rotates along with the rotary shaft 30 and reaches the one-dot chain line in FIG. 2, the chute 74 is passed through the arm body 35 of the arm 32 to supply one ball 2.

The state shown by the solid line in FIGS. 1 to 4 shows a state in which the arm 32 is stationary as a result of being biased by the spring means 47 via the rotary shaft 30, and at this time, the arm 32 is moved forward and downward from the rotary shaft 30. The member to be braked 59 is frictionally joined to the friction material 69. When the electric motor 39 is driven from this state, the arm 32 moves along with the rotating shaft 30 against the urging force of each spring 56 and the frictional force of the braked body 59 against the friction material 69, and the arm 32 moves along the arrow B in FIG. Rotate backward and upward as indicated by.

When the arm 32 is located at the position indicated by the alternate long and short dash line in FIG. 2, the ball 2 is supplied through the chute 74 to the ball receiving portion 36 of the arm 32. Further, by driving the electric motor 39, the arm 32 rotates forward and upward as indicated by an arrow C in FIG. When this arm 32 reaches the position shown by the chain double-dashed line in FIG. 2 above, the direction of the urging force by the spring means 47 passes through the center of the rotary shaft 30, and at this time, the rotary shaft 30
The biasing force of the spring means 47 that tries to rotate is zero.

When the electric motor 39 is further driven from the above state, as shown by an arrow D in FIG. 2, thereafter, the arm 32 momentarily rotates forward and downward with the rotating shaft 30 by the urging force of the spring means 47. To do. At this time, the power transmission by the one-way clutch is automatically disengaged, and the arm 32 instantaneously rotates forward and downward regardless of the power of the electric motor 39. Then, by the rotation of the arm 32, the ball receiving portion
The ball 2 placed at 36 is pitched forward as indicated by an arrow D in FIG.

In the above case, since the arm 32 is provided between the left and right springs 56, 56, the left and right springs 56, 56 urge the rotating shaft 30 on both sides of the arm 32. In left 30, right and left springs 56, 56 from the position biased to the position where the arm 32 is attached, the twists generated in the left and right parts are opposite to each other, that is, the rotation shaft 30 to which the arm 32 is attached. Twisting of the part is suppressed.

Therefore, it is possible to prevent the arm 32 from rotating around the axis of the arm 32 due to the twist of the rotary shaft 30, and to accurately perform the pitching by the arm 32.

Also, after the above pitching, the arm 32, which has swung toward the front lower direction, reaches the end of the angular range biased by the spring means 47, that is, reaches the state shown by the solid line in FIG.
Further rotation past this and further rearward rotation causes the spring means 47 to
The urging force of (1) acts in the opposite direction to the previous one, and tries to rotate the arm 32 in the direction opposite to the above-mentioned rotation direction, and therefore, shocking vibration is likely to occur in this arm 32. However, in the above configuration, when the arm 32 reaches the end of the angular range biased by the spring means 47, the braked body 59 is frictionally joined to the braking body 64 to brake the rotation of the arm 32 together with the rotating shaft 30. Therefore, the vibration is prevented from occurring.

In the above case, the braked body 59 is arranged between the left and right springs 56, 56. Therefore, the braking force of the braked object 59 on the rotating shaft 30 acts between the left and right springs 56, 56, and thereby the shearing force generated on the rotating shaft 30 is suppressed to be small.

Further, the braked body 59 is an arc-shaped braked body in which the arm 62 protruding from the rotating shaft 30 and the outer peripheral surface of the arm 62 frictionally bonded to the braking body 64 are provided as described above. Department
It is made up of 63 and is lightweight.

Then, as described above, by making the rotating shaft 30 and the braked body 59 lighter, the inertial force when rotating is reduced, and the braking force in the case of trying to brake the rotation of the arm 32 is reduced accordingly. Is done.

Hereinafter, the above operation is repeated by continuously driving the electric motor 39, and pitches are performed at regular intervals.

Further, if the gantry 6 is set to a predetermined angle by the angle adjusting device 18, it is possible to obtain a desired pitch angle in the vertical direction. Further, the vibration generated on the pedestal 6 during pitching is absorbed by the lower spring 25 and the upper spring 26.

FIG. 5 shows the braking device 58 in more detail.

That is, the arcuate convex surface 63a of the braked portion 63 is formed with a smaller radius of curvature than the arcuate 75 centered on the axial center of the rotating shaft 30, and the arcuate convex surface 63a is forward in the rotational direction of the braked portion 63. It is formed so as to gradually approach the rotating shaft 30 as it goes to, in other words, away from the arc 75.

Therefore, when the braked body 59 is about to start friction bonding to the braking body 64, this bonding is performed smoothly, and thus the impact force when the braked body 59 collides with the braking body 64 is suppressed to a small level. To be

According to the present invention, when the braked body is frictionally joined to the braked body, the braked body is pressed against the braked body by the elastic force of the spring. Even if the joint surface is worn to some extent, the frictional joint force of the braked body with respect to the brake body is maintained at a predetermined value by the elastic force.

Therefore, the work for keeping the frictional joining force between the braked body and the braking body at a predetermined value does not have to be as frequent as in the conventional case,
To that extent, this work becomes easier.

Further, when the braked body that rotates along with the rotation axis tries to frictionally join the braked body and the braked body collides with the braked body, an impact force is generated, which is absorbed by the spring.

Therefore, it is suppressed that the joint surfaces of the braked body and the brake body are consumed by the impact force, that is,
An increase in the service life of the braking device is achieved.

The braked body is composed of an arm protruding from the rotary shaft, and a braked portion having an arcuate side view whose outer peripheral surface is frictionally joined to the brake body.

For this reason, weight reduction can be achieved as compared with the conventional case where the braked body is composed of a drum and there are many wasted parts.

Therefore, since the rotating shaft and the braked body can be lightened,
The inertial force when it rotates can be reduced, and the braking force when braking the rotation of the arm can be reduced accordingly. That is, since the frictional joining force of the braked body with respect to the braking body can be reduced, the wear of the braking device can be suppressed, and the life of the braking device can be improved in this respect as well.

Further, the braked portion is formed so as to gradually approach the rotating shaft as it goes forward in the rotation direction of the braked portion.

For this reason, when the braked body starts to frictionally bond to the brake body as the braked body rotates, the pressure contact force of the braked part of the braked body with respect to the brake body gradually increases, so that this bonding is performed smoothly. .

Therefore, as described above, the braked portion is provided at the protruding end of the arm and is present only in a part of the circumferential direction of the rotating shaft, but the impact when the braked portion collides with the braking body is Power can be kept small.

As a result, it is further suppressed that the joint surfaces of the braked body and the braked body are consumed by the collision, and the life of the braking device is improved.

[Brief description of drawings]

1 is a front view, FIG. 2 is a side view, FIG. 3 is a partially enlarged view of FIG. 1, and FIG.
Fig. 5 is a partial cross-sectional view taken along the line IV-IV of the drawing, and Fig. 5 is a more detailed view of the body to be braked. 1 ... Pitcher, 2 ... Ball, 6 ... Stand, 30 ... Rotating axis,
32 …… Arm, 36 …… Ball receiver, 47 …… Spring means, 56 ……
Spring, 58 ... Braking device, 59 ... Braking object, 62 ... Arm, 63 ... Braking part, 64 ... Braking object, 71 ... Spring.

Claims (1)

[Scope of utility model registration request] 1. A rotary shaft having a horizontal axis is supported on a gantry, an arm is projectingly provided on the rotary shaft, and a ball receiving portion for mounting a ball for pitching is provided at a protruding end of the arm. A spring means for urging the arm in one direction via a rotation shaft is provided in a partial angular range of the entire circumference, and rotation of the arm by this urging causes a ball on the ball receiving portion to be pitched. A braking body is attached to the rotating shaft, a braking body is attached to the pedestal side so as to correspond to the braking body, and when the arm reaches the end of the angular range by being biased by spring means, the braking body is In a pitching mechanism of a pitcher for baseball practice that is frictionally joined to a braking body, when the braked body is frictionally joined to the braking body, the braking body is brought into pressure contact with the braked body by an elastic force of a spring, An arm having the braked body projecting from a rotary shaft, and the arm Its outer peripheral surface is provided on the projecting end is constituted by the side view arcuate braked portion frictionally joined to the braking body,
A pitching mechanism for a baseball practice pitching machine in which the braked portion is formed so as to gradually approach the axis of rotation as the braked portion rotates forward.