JP2514191Y2 - Belt sander - Google Patents

Description

[Detailed description of the device]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a belt sander having an improved structure for supporting a workpiece during grinding.

[0002]

2. Description of the Related Art As a belt sander used for grinding woodwork materials, resin materials, etc., for example, the following structures are known.

An endless sanding belt is stretched over the upper portion of the main frame between rolls, which is driven by a drive motor. On the other hand, a material feeding belt is laterally extended and hung around the lower portion of the main frame, and the work placed on the material feeding belt is fed so as to pass below the sanding belt. Then, a pad is provided on the back surface side of the sanding belt to press the sanding belt against the work on the material feeding belt, and a support table is provided on the back surface side of the material feeding belt. When the work is fed to the grinding area by the material feeding belt, the sanding belt is pressed against the surface of the work by the pad, and the downward force acting on the work is received by the support table to a predetermined grinding pressure.

In this type of belt sander, if the dimension between the pad and the support table is fixed, if the thickness of the work varies, the "cutting margin" from the surface of the work varies. Not preferable.

Therefore, for example, Japanese Patent Laid-Open No. 63-221960.
By supporting the support table with an air spring as described in Japanese Patent Publication No. JP-A-2003-242242, for example, when a work having a large thickness is sent, the air spring is compressed to sink the support table downward, Therefore, a structure for preventing excessive cutting is considered.

[0006]

However, in the structure in which the support table is supported in a floating state by the air spring as described above, when a work having a large thickness enters the support table, one end of the support table Since only the side (entry end side) is pushed down, the supporting table is slightly tilted and the prying force acts,
As a result, smooth up and down movement of the support table may be hindered.

In order to prevent this and smoothly move the support table up and down according to the thickness of the work, it is necessary to provide a guide mechanism for guiding the up and down movement of the support table.
However, such a guide mechanism has the drawback that the structure is considerably complicated due to the large size of the supporting table.

On the other hand, instead of the support table, a structure in which a support roll is provided below the pad and the pivot of the support roll is supported by a spring so as to be movable up and down is also considered. In this way, the structure in which the pivot is supported so that it can move up and down has the advantage that the structure is significantly simpler than the structure in which the entire large support table is supported so that it can move up and down.

However, this has the following drawbacks.
That is, in this configuration, the grinding pressure acting between the work and the sanding belt depends on the compression amount of the spring. Therefore, in a work having a thickness larger than the standard, the spring is compressed more than the standard, so that the grinding pressure becomes large and the "cutting margin" becomes larger than the standard value. On the other hand, when a work having a thickness less than the standard enters, the compression amount of the spring is reduced, the grinding pressure is reduced, and the "shaving margin" is less than the standard value.

The present invention has been made in view of the above circumstances, and an object thereof is to have a simple structure and to keep the grinding pressure constant even if there is a variation in the thickness dimension of the work, thereby improving the grinding quality. There is a belt sander that can be done.

[0011]

The belt sander of the present invention is an endless sanding belt that is run by being stretched between a plurality of rolls, and a feeding belt that feeds a work to be ground into a grinding area by the sanding belt. And a treading member that is provided on the back side of the sanding belt and presses the sanding belt against the workpiece fed by the material feeding belt, and is provided so as to contact the back surface of the material feeding belt at a position corresponding to the treading member. The pressure roll, a pivot guide member for movably guiding the pivot of the pressurizing roll in a direction of moving toward and away from the work, and the back side of the material feeding belt located before and after the pressurizing roll in the work moving direction are in contact with each other. It is possible to move the guide roll provided like this and the pivot of this guide roll in the direction parallel to the moving direction of the pressurizing roll and toward and away from the work. And a cylinder device that is connected to the pivot shaft of the pressurizing roll and that can press the pressurizing roll with a constant pressure in a direction approaching the work, and a cylinder device for the pressurizing roll. And a cylinder device which is connected to the pivot of the guide roll and can press the guide roll in a direction approaching the work with a constant pressure.

[0012]

The work is sent by the material feeding belt to the grinding area by the sanding belt, passes through the guide roll and reaches the top of the pressurizing roll. The guide roll and the pressurizing roll are urged toward the work by a cylinder device. Therefore, the work is pushed by the pressure roller from the back side of the material feeding belt, and the surface of the work is pressed against the sanding belt supported by the treading member, and the grinding progresses.

Here, the pivot of the pressurizing roll is movably supported in the direction of coming into contact with and separating from the work, and by moving this, the work is pressed against the sanding belt with a predetermined pressure. Therefore, for example, when a work having a large thickness is fed, the pressure of the cylinder device does not change although the pressurizing roll moves in the direction away from the sanding belt, so that the grinding pressure applied to the work does not change. On the other hand, when a work having a small thickness is fed, the amount of movement of the pressurizing roll decreases, but the pressure of the cylinder device does not change, so that the grinding pressure applied to the work does not change. As a result, the grinding pressure can be kept constant regardless of variations in the thickness of the work.

Further, in the above-mentioned means, the guide roll is provided movably in the front and rear of the pressurizing roll in the work moving direction similarly to the pressurizing roll, and this is also biased by the cylinder device. Therefore, for example, when a work having a small thickness is fed, the movement amount of the pivot of the guide roll is reduced to the same extent as that of the pressurizing roll. This means that the work is always sent to the grinding area by the sanding belt without tilting.

If the guide roll is fixed and only the pressurizing roll is moved by the cylinder device, the following problems occur. That is, when a work thinner than the standard is fed, the pressurizing roll 1 is positioned higher than the guide roll 2 as exaggeratedly shown in FIG. Therefore, a so-called “edge sag” phenomenon occurs in which the work 3 tilts downward to the right and the ridge A at the leading end in the approach direction is excessively ground by the sanding belt 4.

In this respect, according to the structure of the above means, even if the thickness of the work varies as described above, the work is always fed below the sanding belt without tilting. It is more convenient to improve the grinding quality by preventing the occurrence of the “sag” phenomenon.

[0017]

[Effects of the Invention] The effects of the present invention are as follows.

Since the pivot of the pressurizing roll moves according to the thickness of the work and the work is constantly pressed against the sanding belt by the cylinder device at a predetermined pressure, the grinding pressure becomes constant and "shave". The fluctuation of can be suppressed. Also, not only the pressure roll but also the guide rolls located before and after the pressure roll move in the same way as the pressure roll, and the work is always sent to the grinding area by the sanding belt without tilting, so that the "edge sagging" phenomenon does not occur. It can be prevented and the quality of grinding is greatly improved as a whole.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment embodying the present invention will be described below with reference to the drawings.

As shown in FIGS. 1 and 2, the overall construction comprises a work transfer mechanism 10 and a sanding mechanism 50 provided above it. In the work transfer mechanism 10,
The material feeding belt 11 is provided so as to extend in the left-right direction in FIG.

<Sanding Mechanism> First, the sanding mechanism 50 will be described. this is,
The support posts 51 are provided so as to straddle the material feed belt 11 above the work transfer mechanism 10 and are entirely covered by a protective cover 52. By rotating the operation handle 53, the sanding mechanism 50 can be moved to a desired height along the support post 51.

Inside the protective cover 52, the upper roll 5
4 and 2 lower rolls 55a, 55b are provided,
An endless sanding belt 56 is stretched between these. The sanding belt 56 is driven by a motor (not shown) and travels in the direction of arrow B, which is the opposite direction to the traveling direction of the material feeding belt 11 (direction of arrow A in the figure).

A pad 57, which is a pedaling member, is provided between the two lower rolls 55a and 55b. This is located on the back side of the sanding belt 56 and has a function of urging the sanding belt 56 downward.

Two pressing rolls 58a, 58b, 59a, 5 are provided on both left and right sides of the lower rolls 55a, 55b.
Although not shown, a pivot shaft 9b is supported so as to be vertically movable, and is urged downward by a compression coil spring.

An air intake duct of a dust collector (not shown) is provided as an opening in the protective cover 52 of the sanding mechanism 50 so that the chips of the work generated during grinding are sucked together with the air. There is. An inspection door 60 is attached to the front surface of the protective cover 52 so as to be openable and closable.

<Work Transfer Device> Next, the work transfer device 10 will be described. This is a configuration in which a pair of front and rear side frames 13 are fixed to the upper part of a base 12 installed on the floor surface, and feed rolls 14 are rotatably attached to both left and right ends of the side frame 13. The material feeding belt 11 is stretched between the rolls 14, 14. The material feeding belt 11 is made to travel at a low speed in the direction of arrow A by a known drive mechanism provided in the base 12, and a work is placed on the upper surface of the material feeding belt 11 from the right side of the apparatus to the sanding belt 5
It is designed to be fed to the grinding area below 6.

Between the pair of feed rolls 14 and 14, one pressurizing roll 15 and five guide rolls 16 are provided across the side frame 13. Of these, the pressurizing roll 15 is positioned immediately below the pad 57. Further, three of the guide rolls 16 are located on the work entry side of the pressurizing roll 15, and are located immediately below the lower roll 55b on the right side of the sanding mechanism 50 and the two press rolls 58a, 58b. The remaining two rolls are on the discharge side of the work from the pressurizing roll 15 and are positioned corresponding to the two holding rolls 59a and 59b.

The support structure for each of these rolls will be described. First, the pressurizing roll 15 will be described. As shown in FIG. 3, a bearing 18 is attached near each end of a fixed shaft 17 as a pivot, and a cylindrical roll main body 19 is attached to an outer race 18a of the bearing 18.
It is configured by fitting. With this configuration, the roll main body 1
9 is rotatably supported with respect to the fixed shaft 17, and square column portions 17a are formed at both ends of the fixed shaft 17 by cutting as shown in FIG.

On the other hand, a pivot guide member 20 is attached to the side frame 13 with two bolts 21. Each bolt insertion hole 2 formed in the pivot guide member 20
Reference numeral 0a denotes an oval shape that is long in the workpiece conveying direction, and therefore the fixing position of the pivot guide member 20 is set to the side frame 13
On the other hand, it can be adjusted along the direction in which the work is conveyed. A pair of guide projections 20b are provided on the lower surface of the pivot guide member 20 so as to project downward at predetermined intervals, and the prismatic portions 17a at both ends of the fixed shaft 17 are fitted between the guide projections 20b. ing. As a result, the fixed shaft 17 and thus the pressurizing roll 15 are supported by the pivot guide member 20 so as to be movable up and down, and the fixing position of the pivot guide member 20 is adjusted to adjust the mounting position of the pressurizer roll 15 to the work. It is possible to adjust in the direction along the conveyance direction of (1) (left and right in FIG. 1).

A cylinder device 22 is provided below the pivot guide member 20 and is fixed to the lower surface of each guide projection 20b of the pivot guide member 20 by a bolt (not shown). The rod 22a of the cylinder device 22 protrudes between the guide protrusions 20b of the pivot guide member 20, and the tip of the rod 22a supports the prism portion 17a of the fixed shaft 17. Therefore, when the cylinder device 22 is operated to change the protruding amount of the rod 22a, the fixed shaft 17 and thus the pressurizing roll 15 move up and down. The cylinder device 22 receives a supply of compressed air of a constant pressure from the air compressor side (not shown), and has a function of constantly urging the rod 22a upward with a constant pressure. The air pressure supplied to the cylinder device 22 can be adjusted by a valve device (not shown), but since a specific structure for this is well known to those skilled in the art, the description thereof will be omitted.

A stopper mounting member 23 is superposed on the pivot guide member 20 and is fixed to the pivot guide member 20 by two bolts 24. A screw hole 23a is formed in the center of the stopper mounting member 23, and a bolt insertion hole 20c is formed in the pivot guide member 20 at a position corresponding to the screw hole 23a. The stopper bolt 25 is inserted into the screw hole 23a of the pivot guide member 20.
Is screwed in, and its tip can enter into the stopper receiving hole 26 formed on the upper surface of the prismatic portion 17 a of the fixed shaft 17. As a result, the rising limit position of the fixed shaft 17, and thus the pressurizing roll 15, is restricted.

Since the support structure of the pressurizing roll 15 described above is the same at both ends of the fixed shaft 17, the description of the support structure at the other end is omitted.

Next, the support structure of the guide roll 16 will be described. The structure of the guide roll 16 itself is the same as that of the pressurizing roll 15 described above, and since the roll main body is fitted to the fixed shaft 31 via the bearing, detailed illustration is omitted. The support structure is as shown in FIGS. 5 and 6,
Similar to that of the pressure roll 15, but with a pivot guide member 32
Is not adjustable in the direction (left-right direction) along the work transfer direction.

More specifically, the pivot guide member 32 is fixedly attached to the side frame 13 via a bolt 33, and the pair of guide protrusions 3 formed on the lower surface thereof.
The end of the fixed shaft 31 of the guide roll 16 is inserted between the four. The end of the fixed shaft 31 is also received and supported by the rod 35a of the cylinder device 35, and when the cylinder device 35 is operated to change the protrusion amount of the rod 35a, the fixed shaft 31 and thus the guide roll 16 are moved up and down. be able to. Further, the cylinder device 35 also has a function of being supplied with compressed air having a constant pressure and always urging the rod 35a upward with a constant pressure. The air pressure supplied to the cylinder device 35 can be adjusted independently of the air pressure supplied to the cylinder device 22 that receives the pressurizing roll 15.

A stopper mounting member 36 is fixed on the pivot guide member 32 by a bolt 37 as shown in FIG. 6, and a stopper bolt 38 is screwed into a screw hole 36a formed therein. The tip of the stopper bolt 38 can enter into the stopper receiving hole 39 formed on the upper surface of the fixed shaft 31, and thereby the upper limit position of the fixed shaft 31 and thus the guide roll 16 is regulated. ing.

The support structure at each end of the guide roll 16 described above is common to the left and right, and the same applies to the remaining four guide rolls 16, so description thereof will be omitted.

Next, the operation of this embodiment will be described.

First, the operating handle 53 provided on the sanding mechanism 50 is operated to move the sanding mechanism 50 to a desired height. This height is determined in consideration of the thickness of the work and the necessary "cutting margin", and can be set while looking at a known gauge (not shown).

Thereafter, the work transfer device 50 is activated,
The work to be ground is placed on the material feeding belt 11 and fed below the sanding mechanism 50. Then, first, the tip of the work reaches the position sandwiched between the guide roll 16 and the pressing rolls 58a and 58b, and when further fed, reaches the position sandwiched between the pad 57 and the pressurizing roll 15. When reaching this position, the surface of the work is rubbed by the sanding belt 56, so that the work is ground and scraped by a predetermined "shaving margin". This grinding state continues until the rear end of the work comes out of the position between the pad 57 and the pressurizing roll 15, and the entire surface of the work is ground during that time.

By the way, in the above-mentioned grinding state, a force for pressing the sanding belt 56 from the pad 57 acts on the work, and the force is received by the pressurizing roll 15 located immediately below the pad 57. Therefore, the grinding pressure acting on the work depends on the air pressure supplied to the cylinder device 22 that biases the pressurizing roll 15 upward. In the present invention, the air pressure supplied to the cylinder device 22 is constantly maintained so that the grinding pressure is always constant.

Further, it is assumed that a work thinner than the standard is supplied due to variations in the thickness of the work. Then, in this case, the guide rolls 16 and the pressurizing rolls 15 are raised by the cylinder devices 22 and 35, and the work is ground without forming a gap between the sanding belt 56 and the work. In addition, since the air pressure supplied to the cylinder device 22 is always maintained at a constant pressure as described above, the cylinder device 22 and the pressurizing roll 15 press the work against the sanding belt 56 at a constant pressure, thereby grinding. The pressure can be the same as for a standard thickness work.

On the other hand, when a work having a size thicker than the standard is supplied, each guide roll 16 and the pressurizing roll 15 are pushed by the work and move downward, so that a gap with the sanding mechanism 50 is generated. Grinding is performed with the dimensions increased. Further, since the air pressure supplied to the cylinder device 22 is maintained at a constant value even in this case, the pressurizing roll 15 presses the work against the sanding belt at a constant pressure, and the grinding pressure is also changed to the work having the standard thickness. Can be the same.

Therefore, according to the belt sander of the present invention, the grinding pressure acting between the sanding belt 56 and the work becomes constant even if the thickness of the work varies, and the "shaving margin" becomes constant. Can be In addition, in order to increase the grinding pressure and increase the "shaving margin", the supply pressure to the cylinder device 22 may be adjusted to be high.

Further, in the belt sander of the present embodiment, not only the pressurizing roll 15 but also a total of five guide rolls 16 positioned in front of and behind the pressurizing roll 15 are moved up and down by the cylinder device 35. Therefore, for example, when a work thinner than the standard is fed, the guide roll 16 as well as the pressurizing roll 15 rises, and the work is fed below the sanding belt 56 while always maintaining a horizontal state without tilting. become. For this reason, if the workpiece is fed in a state of falling to the right as shown in FIG. 7, a so-called "edge sagging" phenomenon occurs in which the ridge at the leading end in the approach direction is excessively ground by the sanding belt. However, with the belt sander of the present invention, such "edge sagging" can be reliably prevented.

As described above, according to this embodiment, the pressurizing roll 15 moves up and down according to the thickness of the work, and the work is constantly pressed against the sanding belt 56 by the cylinder device 22 at a predetermined pressure. Can be kept constant and fluctuations in the "cutting margin" can be suppressed. Further, not only the pressurizing roll 15, but also the guide rolls 16 positioned before and after the pressurizing roll 15 move up and down similarly to the pressurizing roll 15 and the work is always fed below the sanding belt 56 without tilting, so that "edge drooping" occurs. This can prevent the occurrence of phenomena and greatly improve the grinding quality as a whole.

The present invention is not limited to the embodiments described above and shown in the drawings. For example, the pad is not provided as a treading member, and it is used as a treading member by urging the lower roll downward. It can be applied to a drum head type belt sander with the above configuration, or can be applied to a belt sander in which the sanding belt is located on the lower surface of the work and presses the work from above with support rollers. Various modifications can be made within the range.

[Brief description of drawings]

FIG. 1 is an overall front view showing an embodiment of the present invention.

[Figure 2] Side view of the same

FIG. 3 is an enlarged vertical side view of a main part.

FIG. 4 is an enlarged plan view of the same.

5 is a vertical cross-sectional view taken along the line AA of FIG.

6 is a vertical cross-sectional view taken along line BB of FIG.

FIG. 7 is a schematic front view for explaining a defect of a virtual comparison example.

[Explanation of symbols]

 10 ... Work transfer mechanism 11 ... Material feeding belt 14 ... Roll 15 ... Pressurizing roll 16 ... Guide roll 17 ... Fixed shaft (pivot shaft) 22, 35 ... Cylinder device 31 ... Fixed shaft (pivot shaft) 50 ... Sanding mechanism 56 ... Sanding belt 57 ... Pad (pedaling member)

Claims (1)

(57) [Scope of utility model registration request] 1. An endless sanding belt which is stretched between a plurality of rolls and runs, a material feeding belt which feeds a work to be ground into a grinding region by the sanding belt, and a rear surface side of the sanding belt. And a pressing roller that presses the sanding belt against the work sent by the material feeding belt, and a pressure roller provided at a position corresponding to the foot pressing member and in contact with the back surface of the material feeding belt. A pivot guide member for movably guiding the pivot of the pressure roll in the direction of approaching and separating from the work, and a front side and a rear side of the pressurizing roll in the work moving direction, provided so that the back side of the material feeding belt is in contact. And a guide roll that can be moved in a direction parallel to the moving direction of the pressurizing roll and in a direction of approaching and separating from the work. And a cylinder device that is connected to the pivot shaft of the pressurizing roll and can press the pressurizing roll with a constant pressure in a direction of approaching the work, and a cylinder device for the pressurizing roll. A belt sander comprising a cylinder device which is separately provided and connected to a pivot of the guide roll, and which can press the guide roll in a direction approaching the work with a constant pressure.