JPH0623413Y2 - Roller belt sanda - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial field of application> The present invention relates to a roller belt sander that presses an endless polishing belt circulating between two rollers against a workpiece to perform polishing.

<Prior Art> Conventionally, the belt type sander as described above has been used for polishing, rust removal, coating film removal, etc. of woodwork, metal or vehicle. For example, the sponge type portable polishing apparatus described in Japanese Utility Model Laid-Open No. Sho 63-30464 is one example.

In the polishing apparatus, a contact wheel and a tension pulley are provided in parallel with each other on an elongated frame, and the contact wheel is provided with a sponge on the outer circumference. An endless polishing belt is hung between the contact wheel and the tension pulley, and the polishing belt circulates when the contact wheel is driven by a drive motor. In addition, the main handle on the rear end side of the above frame,
Further, auxiliary handles are attached to the tip end side, respectively, and an operator grips the main handle and the auxiliary handle with both hands and presses the circulating polishing belt against the work piece at the contact wheel portion to perform work such as polishing.

When the contact wheel having the sponge as described above is used, the elasticity of the contact wheel causes a certain tension in the polishing belt, so that a tension applying device using spring means or the like is unnecessary, and the contact wheel is pressed when the polishing belt is pressed. Since it adapts itself to the shape of the object due to its elasticity, it is possible to polish not only a flat surface but also a curved surface.

<Problems to be Solved by the Invention> However, in the above-described polishing apparatus, it is difficult for an operator to work with both hands while grasping the main handle and the auxiliary handle, and it is difficult to work with one hand. In addition, an electric motor is generally used as the drive motor, but the weight thereof is heavy, and this is one of the factors that hinder the one-handed work.

<Means for Solving the Problems> The present invention has been made in view of the above circumstances, and a roller belt sander according to the present invention includes a body frame, an elastic wheel, a tension pulley, and
A polishing belt and an air motor are provided.

The elastic wheel is provided with a sponge-like elastic layer on the outer circumference and is rotatably attached to a position near the lower end of the frame.

The tension pulley is rotatably attached to the main body frame at a predetermined distance rearward from the elastic wheel.

The polishing belt has an endless shape and is hung on the elastic wheel and the tension pulley.

The air motor is provided on the main body frame and rotationally drives the elastic body wheel.

The motor case that constitutes the outer shell of the air motor is a gripping grip that is protruded from the main body frame above the polishing belt and extends rearward to be gripped by an operator. In addition, the motor case, which is the gripping grip, is rotatable about one axis with respect to the main body frame and is fixed at an arbitrary angular position, and an auxiliary grip is provided above the front end of the main body frame. The mounting position is adjustable.

<Operation and Effect> In the roller belt sander as described above, when the elastic body wheel is rotationally driven by the air motor, the polishing belt circulates between the elastic body wheel and the tension pulley, and the gripping grip that is the motor case portion is secured. The work is performed while being held by the operator.

By using the air motor, the motor part has a small diameter and is lightweight, and the sander is downsized and lightweight as a whole. The motor case of the small-diameter air motor is also used as the grip grip, and in combination with the above-described weight reduction, the operator can perform one-handed operation while holding the grip grip. Moreover, since the fixed position of the grip that is the motor case can be changed around the uniaxial line,
The most suitable grip position can be selected according to the type of work. Since the one-handed operation as described above can be performed, the work corresponding to the complicated shape can be performed.
Further, by holding the auxiliary sander with the adjusted mounting position and the gripping grip and holding the belt sander with both hands, it becomes possible to stably apply a load to the polishing belt and perform a delicate operation. .

<Embodiment> Hereinafter, one or two embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a front sectional view of a roller belt sander according to an embodiment of the present invention, and FIG. 2 is a rear view thereof. As you can see from these figures, this roller belt sander
A body frame 2 that is substantially L-shaped when viewed from the front, an elongated cylindrical air motor 4, a planetary gear device 6 as a reduction mechanism, a sponge wheel 8 as an elastic wheel,
A tension pulley 10 provided in parallel with the tension pulley 10 and an endless polishing belt 12 hung around the sponge wheel 8 and the tension pulley 10 are provided.

As is clear from FIG. 1, the air motor 4 has an outer shell mainly composed of a substantially cylindrical motor case 14, and a cylinder 16 is fixed inside the outer shell. The rotor 18 is eccentric in the inner circumferential surface of the cylinder of the cylinder 16,
In addition, a part of the outer peripheral surface of the cylinder 16 is rotatably arranged so as to be in close proximity to the inner peripheral surface of the cylinder 16. The rotor 18 is
A plurality of blades (vanes) 20 are held at equal angular intervals so that they can move in and out.
The space inside the cylinder 16 is divided into a plurality of air chambers by 0.

An air hose 22 extending from an unillustrated pressurized air source is connected to the motor case 14 via a hose joint 24, and an air passage extending from the hose joint 24 to the supply air chamber 26 is formed in the motor case 14. However, an air valve 28 is provided on the way of this air passage. The air valve 28 is provided with a valve rod 32 having an O-ring 30 mounted thereon. The valve rod 32 is slidably fitted in a valve cylinder 34 and is biased to a valve closed position by a spring 36. . The valve rod 32 projects outside the motor case 14 and contacts the lever 38. One end of the lever 38 is a pin 39
Is rotatably attached to one end of the motor case 14, and the free end side extends long to the other end side of the motor case 14.

By rotating this lever 38 downward in FIG. 1, the valve rod 32 is moved against the spring force of the spring 36, and the pressure air from the air hose 22 passes through the valve 28 and the supply air chamber 26. To the rotor 1 from a supply port (not shown)
8 is given a rotational force. After that, the pressure air is guided to the discharge passage 40 from a discharge port (not shown), further passes through the exhaust hose 42, and is discharged rearward from the rear end. The exhaust hose 42 is attached to one end of the motor case 14 via an exhaust cover 44.

The end plates 46,
48 is fixed, and the end plate 4 is integrated with the rotor 18.
A rotor shaft 50 extends rotatably through 8 and a sun gear 52 of the planetary gear device 6 is formed at the tip of the rotor shaft 50. A plurality of planetary gears 54 mesh with the sun gear 52, and the planetary gears 54 also mesh with the internal gear 56 in an inscribed state. The internal gear 56 is fixed to the opening of the other end of the motor case 14 by screwing, and a spindle 58 is concentrically and rotatably held inside the internal gear 56 with the rotor shaft 50. The plurality of planetary gears 54 described above are rotatably supported by pins 60 on flange portions formed at one end of a spindle 58. Therefore, when the rotor shaft 50 rotates, the planetary gear 54 revolves around the sun gear 52 while rotating along the internal gear 56, and as a result, the spindle 58 rotates according to the reduction ratio given by those gear ratios.

A bevel gear 62 is fixed to the spindle 58, and this bevel gear 62 is meshed with a bevel gear 64 that constitutes a part of a rotation transmission system to the sponge wheel 8. The bevel gears 62 and 64 are housed in a gear case 66, and the gear case 66 is fixed to the internal gear 56 by a cap nut 68 and is integrated with the motor case 14.

As is apparent from FIG. 3, the gear case 66 is rotatably fitted in a circular fitting hole 70 formed in the upper portion of the main body frame 2, and is set by the set screw 72.
The gear case 66 is fixed at an arbitrary angular position, and an annular groove 74 to which the set screw 72 is pressed is formed in the fitting outer peripheral portion of the gear case 66. That is, the air motor 4 shown in FIG. 1 is attached to the main body frame 2 via the gear case 66 in a state where its fixed angular position can be adjusted. The motor case 14 of the air motor 4 serves as a grip grip to be gripped by the operator, in other words, the motor case 14 also serves as the grip grip. A soft ring-shaped hand pad 76 made of, for example, sponge is attached near the end of the motor case 14.

An auxiliary grip 78 is fixed to the gear case 66, so that not only one-handed operation but also two-handed operation with the motor case (holding grip) 14 being held is possible. The auxiliary grip 78, as is clear from FIG.
It is formed integrally with the circular ring-shaped grip arm 80,
The grip arm 80 is provided in the groove 7 of the gear case 66.
It is rotatably fitted to a circular outer peripheral surface formed at the end opposite to 4, and is fixed at an arbitrary angular position by a set screw 82.

Bevel gear 64 meshing with bevel gear 62 shown in FIG.
Is fixed to one end of the gear shaft 84 as is apparent from FIG. 3, and the other end of the shaft 84 is
The timing pulley 86 is fixed. On the other hand, a timing pulley 90 is fixed to a drive shaft 88 parallel to the gear shaft 84, and a timing belt 92 is stretched between the timing pulleys 86 and 90. An idle pulley 94 is rotatably provided between the timing pulleys 86 and 90 by a dry bearing 96, and the idle pulley 94 imparts an appropriate tension to the timing belt 92 as is apparent from FIG. Returning to FIG. 3, the timing pulleys 86 and 90, the idle pulley 94, and the timing belt 92 described above are covered by a belt cover 98, and the belt cover 98 is main body by screws 102, 102 via sleeves 100, 100. It is fixed to the frame 2.

The drive shaft 88 is rotatably supported by the main body frame 2, and on the side of the main body frame 2 of the drive shaft 88 opposite to the timing pulley 90,
The aforementioned sponge wheel 8 is fixed. As is clear from FIGS. 3 and 4, the sponge wheel 8 has a cylindrical sponge layer 106 of a predetermined thickness integrated on the outer side of an inner core body 104 made of hard plastic or the like. In the inner core body 104, the drive shaft 88 is fitted into the drive shaft 88 by the serration coupling 108 so as not to rotate relative to each other, and is fixed by tightening the cap screw 110.

As is clear from FIGS. 1 and 4, the main body frame 2 extends laterally from the vicinity of the sponge wheel 8 in a substantially L-shape, and the tension pulley 10 is provided at the tip end portion thereof with the sponge wheel 8. Drive shaft 88
It is rotatably held around a tension arbor 112 parallel to the. The tension arbor 112 is fixed to the main body frame 2 by tightening the screw member 116 at one end thereof.
An elongated hole 118 is formed in a portion connecting 16 with the sponge wheel 8 and the tension pulley 10, and a knob 120 fixed to the tip of the screw member 116 projects from the elongated hole 118. Therefore, the long hole 1
The fixed position of the tension arbor 112 can be adjusted within a range of 18. Then, the polishing belt 12 is hung across the sponge wheel 8 and the tension pulley 10, and is circulated by driving the sponge wheel 8. The polishing belt 12 has a width substantially the same as the width of the sponge wheel 8. For example, a sandpaper-like belt having predetermined polishing particles adhered to the surface of a base material such as cloth is usually used. A wheel cover 130 is provided so as to cover the upper circuit of the polishing belt 12, and is fixed to the main body frame 2 with a plurality of screws 132.

Further, the main body frame 2 extends a little further downward from the L-shaped tip end portion to which the tension pulley 10 is attached, a guide roller 122 is provided at the lower end thereof, and is rotatably held around a guide arbor 124. ing. As is apparent from FIG. 4, the guide arbor 124 is fixed to the main body frame 2 with the nut 126 in parallel with the tension arbor 112 and the drive shaft 88. The guide roller 122 rolls on the ground surface of the workpiece,
A plurality of annular grooves 128 are formed on the outer peripheral surface thereof.
A ring-shaped guide collar such as an O-ring can be mounted in these annular grooves 128.

Next, the operation and usage of the roller belt sander configured as described above will be described.

First, the attachment and detachment of the polishing belt 12 will be described. By loosening the knob 120 shown in FIG.
The tension pulley 10 is brought closer to the sponge wheel 8 side. In this state, the polishing belt 12 is mounted, the tension pulley 10 is moved to the side away from the sponge wheel 8, and then the knob 120 is tightened to tighten the tension pulley 10.
Set. Here, when tightening the knob 120, the knob 120 may be tightened in a state where the central portion of the tension pulley 10 is pushed backward by a finger and empirically appropriate tension is applied. In a general belt sander, in order to continuously apply tension even after the knob 120 is set, it is necessary to apply a biasing force to the front and rear wheels 8 and 10 away from each other by a biasing device including a spring or the like. The addition of the device causes an increase in weight, but in this embodiment, since the polishing belt 12 is appropriately tensioned only by the elastic action of the sponge wheel 8, a dedicated biasing device is not required and the structure is simple. Can reduce the weight.

Next, the roller belt sander of this embodiment can be operated with one hand (it is also possible to operate with both hands, which will be described later). In the case of one-handed operation, the operator grips the gripping grip that is the motor case 14 with one hand (for example, the right hand), but the adoption of the air motor 4 allows the motor portion to have a small diameter and can be easily gripped with one hand. Easy operation due to weight reduction. For example, as compared with the case of using a general electric motor, the weight of the entire sander is much lighter, for example, from 4 kg to about 2.3 kg by using the air motor 4.

In the case of one-handed operation, the front portion (left side in FIG. 1) of the air motor 4 is gripped due to the center of gravity of the entire sander, but the lever 38 for opening and closing the air valve 28 is extended and the gripping grip ( Since the shape is in accordance with the shape of 14), the grip grip (14) can be gripped together with the lever 38. In addition, since the hand is gripped by one hand, almost all the weight of the sander may be applied to the hand depending on the work, but the hand pad 76 made of an elastic material such as sponge is attached to a part of the gripped portion as described above. Therefore, it is possible to reduce the weight and feel of the hand and reduce hand fatigue. If the grip portion of the grip grip (14) is knurled to prevent slipping, the grip is further stabilized.

When the operator grips the gripping grip (14) together with the lever 38, the valve 28 is opened and pressurized air is supplied from the air hose 22 to the air motor 4 to rotate the rotor 18, and the air discharged from the motor 4 is discharged. It is discharged to the atmosphere from the end of the exhaust hose 42. Here, since such a rear exhaust system is adopted and the exhaust hose 42 (for example, made of polyethylene sheet) having a low resistance to the air flow is adopted, noise which is a problem of a general air motor is reduced. And the harmful effect of exhaust flow is small. Further, since the urethane hose made of a soft material is also used for the air hose 22, the resistance to bending is small and the operation of the sander is easy.

The rotation of the rotor 18 is decelerated by the planetary gear device 6 and further transmitted to the drive shaft 88 by the timing belt 92 shown in FIG. This sponge wheel 8
Is driven to rotate, and the frictional force with the sponge wheel 8 causes the polishing belt 12 in FIG. 1 to circulate in the direction indicated by the arrow in the figure.

Then, the circulating polishing belt 12 of the sponge wheel 8 is pressed against a predetermined object to perform polishing, rust removal, or peeling of the coating film. Since it adapts to the elastic deformation of, it is possible to work not only on a flat surface but also on a curved surface and various other processed surfaces. If a sponge wheel 8 of soft type or relatively hard type is prepared, the sponge wheel 8 can be used properly according to the work.

In addition, when finishing a curved surface or a short surface, the sponge wheel 8 is pressed against the processing surface while the guide roller 122 is floated to perform grinding or the like. The work can be carried out by contacting with 8 to the processing plane. Then, by moving the sander while rolling the guide roller 122, a stable finished surface can be obtained and the work becomes easy. It is preferable to attach an O-ring or the like to the groove 128 shown in FIG. 4 of the guide roller 122, since it is possible to avoid contact between metals and prevent slippage.

Since the operation can be performed with one hand as described above, there is an advantage that the work can be sufficiently performed in a place where the work environment is bad, such as painting off a bridge.

The belt sander in this embodiment can be operated (worked) with both hands. In this case, one hand holds the grip grip (14) of the air motor 4 and the other hand holds the front auxiliary grip 78 to perform the work. That is, either one-handed operation or two-handed operation can be selected according to the type and place of work.

Grip grip of air motor 4, that is, motor case 14
Can change the fixed position around the axis of the gear shaft 84. That is, by loosening the set screw 72 shown in FIG. 3 and rotating the gear case 66 within the fitting hole 70 of the main body frame 2, as shown in FIG. Can be adjusted, and set screw 7 after setting at any angle position.
By tightening 2, it is fixed in that angular position. Therefore, the most suitable angle can be given according to the work form.

Further, in this embodiment, the fixing position of the auxiliary grip 78 mounted on the gear case 66 can be changed. That is, by loosening the set screw 82 shown in FIG. 3 and rotating the annular grip arm 80 with respect to the gear case 66 about the axis of the gear shaft 84, as shown in FIG. The relative angle of the auxiliary grip 78 with respect to the grip (14) can also be adjusted, and after the optimum angle is given according to the work form, it is fixed at that position by tightening the set screw 82.

If the present belt sander is used as a one-handed machine by operation, the auxiliary grip 78 can be used together with the grip arm 80, that is, only the grip grip (14) can be used.

Another embodiment is shown in FIG. 7 and FIG.

In this embodiment, a grinding fluid supply means is added to the belt sander described above. Here, the grinding liquid has a function of cooling, preventing clogging, etc., and water or other suitable liquid is used. That is, as is apparent from FIG. 7, the hose joint 134 is fixed to the main body frame 2, and the flexible supply hose 138 is connected to the hose joint 134 via the cock 136.
38 is connected to a predetermined liquid source such as a pump or a tank. From the hose joint 134, guide pipe 1
The reference numeral 40 extends along the upper surface of the wheel cover 130 toward the front outer peripheral surface of the sponge wheel 8, that is, the front end of the cover 130, and a blowing nozzle 142 is provided at the extended end thereof. As is apparent from FIG. 8, the blow-out nozzle 140 extends close to the outer peripheral surface of the sponge wheel 8 in a direction parallel to the generatrix thereof, has a length substantially the same as the width of the sponge wheel 8, and its length. A plurality of nozzle holes 144 are provided at equal angular intervals in the direction.

Therefore, when the cock 136 is opened, the grinding fluid such as water is guided from the supply hose 138 to the blowing nozzle 142 through the cock 136, the hose joint 134 and the guide pipe 140, and the polishing belt 12 is fed from the vicinity of the front end of the wheel cover 130. It is blown out to. In the case of the present embodiment, the blowing angle is set to be an acute angle with respect to the tangent line at the collision point of the liquid, and is blown obliquely from the rear side with respect to the circulating direction of the polishing belt 12. By such so-called water polishing, it is possible to perform work in a state in which the amount of heat generated and clogging are small with respect to the metal, coating film, stone material or other object to be ground or material to be polished.

In the embodiment described above, the sponge wheel 8 is used as the elastic wheel, but the sponge may be rubber-based or urethane-based, and may be a foam having a single-cell structure or an open-cell structure. . Furthermore, the material of the elastic body is not necessarily limited to sponge, and other appropriate elastic body can be used. Also,
Various types of air motors can be selected from known types, and the reduction mechanism is not limited to the planetary gear device.

In addition, it is needless to say that the present invention can be implemented in various modified modes based on the knowledge of those skilled in the art.

[Brief description of drawings]

FIG. 1 is a front sectional view of a roller belt sander according to an embodiment of the present invention, and FIG. 2 is a rear view thereof. 3 is a sectional view taken along the line III-III in FIG. 2, and FIG.
FIG. 4 is a sectional view taken along the line IV-IV in the figure. FIG. 5 is a diagram for simply explaining the change of the fixed angular position of the gripping grip (motor case), and FIG. 6 is a diagram for simply showing the change of the fixed angular position of the auxiliary grip. FIG. 7 is a rear view showing another embodiment of the present invention, and FIG. 8 is a VIII-VI in FIG.
It is a II sectional view. 2 ... Body frame 4 ... Air motor 6 ... Planetary gear unit 8 ... Sponge wheel (elastic wheel) 10 ... Tension pulley 12 ... Polishing belt 14 ... Motor case (holding grip) 18 ... Rotor 20 ... … Blade 22 …… Air hose 28 …… Air valve 42 …… Exhaust hose 104 …… Inner core body 106 …… Sponge layer (elastic body layer) 122 …… Guide roller 136 …… Cock 138 …… Grinding fluid supply hose 140 …… Induction pipe 142 ... Blowout nozzle

Claims (1)

[Scope of utility model registration request] 1. A main body frame, an elastic body wheel rotatably attached to a position near the lower end of the main body frame and having a sponge-like elastic body layer on the outer periphery thereof, and a predetermined rearward direction from the elastic body wheel. A tension pulley rotatably attached to the body frame at a distance, an endless polishing belt hung on the elastic wheel and the tension pulley, and the elastic wheel provided on the body frame. A motor case that includes an air motor that is rotationally driven, and that constitutes an outer shell of the air motor is provided as a grip grip that is protruded from the main body frame above the polishing belt and extends rearward to be gripped by an operator. In addition, the motor case, which is the grip, is rotatable about one axis with respect to the main body frame. Te is fixed to an arbitrary angular position, moreover,
A roller belt sander in which an auxiliary grip is provided at an upper portion of a front end of the main body frame so that an attachment position can be adjusted.