JP6342252B2 - Sanda - Google Patents

Description

  The present invention relates to a sander that has a base portion that swings and moves by a driving force exerted from a motor that is a drive source, and that polishes a workpiece by a polishing sheet attached to the base portion.

  Conventionally, a sander is known as an electric tool for polishing a workpiece. A conventional sander, for example, as described in Patent Document 1 below, is polished by rotation of a main body portion that houses a motor serving as a driving source and an eccentric shaft that is disposed below the main body portion and is driven by the motor. It is comprised mainly by the base part which performs the rocking motion for.

  In a sander represented by the following Patent Document 1, the main body portion and the base portion that performs a swinging motion are connected by a flexible suspension foot (indicated by “Foot” in the following Patent Document 1). Has been. Specifically, the suspension foot has a plurality of support posts (indicated by “leg shaft” in the following Patent Document 1), and the support portion is elastically deformed so that the base portion is attached to the main body portion. Are connected so as to be able to swing. Moreover, the following patent document 2 is known as a prior art document regarding the structure of a suspension leg.

Japanese Patent Publication No. 06-83952 JP-T-2006-504540

  However, in a sander provided with a suspension foot as described in Patent Documents 1 and 2 described above, a specific support column tends to break early in the plurality of support columns during operation, The durability of the suspension leg was reduced.

  The present invention has been made in view of the above-described problems, and an object thereof is to provide a sander with improved durability of the suspension foot.

A sander according to the present invention is disposed below a main body portion including a motor as a driving source, a rotating shaft driven by the motor, and a housing that houses the motor, and the rotating shaft. A sander comprising: a base portion that performs a swinging motion by rotation of an eccentric shaft that is coupled to the suspension body; and a suspension foot that connects the base portion to the body portion so as to be capable of swinging motion. The base part side connecting part connected to the main body part, the base part side connecting part connected to the base part, the main body part side connecting part and the base part side connecting part are connected, and the base part swings. A plurality of struts that are elastically deformed by movement are integrally formed, and the plurality of struts are formed in a columnar shape, and upper ends of the plurality of struts are on a circumference centering on the rotation axis. The plurality of struts arranged Bottom is arranged on a circumference around the eccentric shaft, further, Ri same diameter der the circumference around the circumference and the eccentricity shaft around said rotating shaft, The upper ends of the plurality of support columns are arranged symmetrically with respect to a straight line in the front-rear direction and the left-right direction passing through the center of the rotation shaft, and the lower ends of the support columns are front-rear direction passing through the center of the eccentric shaft Further, it is arranged symmetrically with respect to the straight line in the left-right direction, and the total number of the columns is 8 or more and a multiple of 4 .

  In the sander according to the present invention, the base portion includes a rectangular pad base, the base portion side connecting portion is connected to the pad base, and the diameter is equal to that of the pad base. It can be greater than the short side length.

  ADVANTAGE OF THE INVENTION According to this invention, the sander which improved durability of the suspension leg can be provided.

It is a left view of the sander concerning this embodiment. It is a longitudinal cross-sectional view which shows the internal structure of the principal part of the sander which concerns on this embodiment. It is AA sectional drawing of FIG. 2, and has shown arrangement | positioning of the upper end of a support | pillar. It is BB sectional drawing of FIG. 2, and has shown arrangement | positioning of the lower end of a support | pillar. It is CC sectional drawing of FIG. 2, and one part is abbreviate | omitted. It is a figure which shows the suspension leg of the sander which concerns on this embodiment, (a) is the perspective view which looked at the suspension leg from diagonally upward, (b) is the perspective view which looked at the suspension leg from diagonally downward. .

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments for carrying out the invention will be described with reference to the drawings. The following embodiments do not limit the invention according to each claim, and all combinations of features described in the embodiments are not necessarily essential to the solution means of the invention. .

  First, the basic structure of the sander according to the present embodiment will be described with reference to FIGS.

  FIG. 1 is a left side view of a sander according to this embodiment. FIG. 2 is a longitudinal sectional view showing the internal structure of the main part of the sander according to this embodiment. FIG. 3 is a cross-sectional view taken along the line AA in FIG. 2 and shows the arrangement of the upper ends of the columns. 4 is a cross-sectional view taken along the line BB of FIG. 2 and shows the arrangement of the lower ends of the columns. FIG. 5 is a cross-sectional view taken along the line CC of FIG. Further, in the present specification, as shown in the drawing, “front, rear, left, right, upper, lower” are defined and described.

  The sander 1 according to the present embodiment is disposed below the main body unit 10 including a motor 11 that is a driving source and a housing 21 that houses the motor 11, and performs a swinging motion by driving the motor 11. And a base portion 50. The housing 21 is a resin molded product with a left and right split structure, and the upper portion of the housing 21 is formed to extend in the front-rear direction from the upper side of the motor 11 as a grip portion 22 for a worker to grip.

  The motor 11 is arranged with the motor shaft 12 in the vertical direction, and the lower portion of the motor shaft 12 is rotatably supported by a bearing 13 supported by a bearing holder 23 fixed inside the housing 21. A fan 14 for cooling the motor 11 is fixed to the motor shaft 12 above the bearing holder 23. An eccentric sleeve 41 having an eccentric shaft portion 42 that is eccentric by a predetermined amount with respect to the motor shaft 12 is fixed to the lower end portion of the motor shaft 12 by screws 15. The symbol e in the figure indicates the amount of eccentricity of the eccentric shaft portion 42 with respect to the motor shaft 12. The eccentric sleeve 41 has a flange portion 43 below the eccentric shaft portion 42, and the flange portion 43 is formed to be deviated on the side opposite to the eccentric direction of the eccentric shaft portion 42 with respect to the motor shaft 12. Has been.

  The base unit 50 is installed on each of the pad base 51, the pad 52 fixed to the lower surface of the pad base 51, and the front and rear of the upper surface side of the pad base 51, for fixing an unillustrated polishing sheet to the base unit 50. And clamping devices 55, 55. As shown in FIG. 4, the pad base 51 is a member formed in a rectangular shape in a top view, and is manufactured by resin molding in the present embodiment. The pad 52 is a substantially rectangular member that is slightly larger than the rectangular pad base 51, and is fixed to the lower surface of the pad base 51 by a plurality of screws. The pad 52 is formed by fixing a metal plate with an adhesive on the upper surface of a sheet made of an elastic member such as rubber.

  A bearing storage hole 51b is formed at the center of the pad base 51, and a bearing 53 is press-fitted and fixed in the bearing storage hole 51b. A presser screw 54 is screwed in the vicinity of the bearing storage hole 51b of the pad base 51, and the head of the presser screw 54 presses the outer ring of the bearing 53, so that the bearing 53 is removed from the bearing storage hole 51b. It is prevented. In addition, it is also possible to employ a configuration in which only the central portion where the bearing storage hole 51b of the pad base 51 is formed is made of metal such as aluminum. When this configuration is adopted, the decrease in the press-fit fixing force of the bearing 53 into the bearing housing hole 51b due to temperature rise can be reduced as compared with the case of resin, so that the bearing 53 can be more securely fixed to the bearing housing hole 51b. Can do. The eccentric shaft portion 42 of the eccentric sleeve 41 is inserted into the inner ring of the bearing 53, and the eccentric sleeve 41 and the inner ring of the bearing 53 are rotated together by tightening the screw 15 screwed into the motor shaft 12. Is configured to do. That is, when the motor shaft 12 of the motor 11 which is a rotating shaft rotates, the eccentric shaft portion 42 of the eccentric sleeve 41 fixed to the motor shaft 12 rotates eccentrically with respect to the motor shaft 12, thereby The part 50 is configured to perform a swinging motion with respect to the main body part 10.

  The sander 1 according to the present embodiment is provided with two suspension legs 30 for connecting the base portion 50 to the main body portion 10 so as to be able to swing. Then, next, in addition to a reference figure, FIG. 6 demonstrates the suspension leg 30 of the sander 1 which concerns on this embodiment.

  Here, FIG. 6 is a view showing the suspension leg of the sander according to the present embodiment, (a) is a perspective view of the suspension leg as viewed from obliquely above, and (b) is a perspective view of the suspension leg from obliquely below. FIG.

  As shown in FIG. 6, the suspension leg 30 of the sander 1 according to this embodiment includes a main body portion side connecting portion 31 connected to the main body portion 10 and a base portion side connecting portion 32 connected to the base portion 50. , 32, and eight support pillars 33 that connect the main body side connecting portion 31 and the base portion side connecting portions 32, 32. The main body side connecting portion 31 includes a plate-shaped portion 31a, boss portions 31b and 31b projecting upward from the upper surface of the plate-shaped portion 31a, and holes 31c and 31c formed in the central portions of the boss portions 31b and 31b. And have. In addition, the base portion side coupling portions 32 and 32 are formed at the centers of the plate-shaped portions 32a and 32a, the boss portions 32b and 32b projecting downward from the lower surfaces of the plate-shaped portions 32a and 32a, and the boss portions 32b and 32b. The screw holes 32c and 32c are formed. The support column 33 is formed as a columnar shape extending in the vertical direction.

  As shown well in FIG. 5, the main body side connecting portion 31 of the suspension leg 30 is formed by inserting boss portions 31 b and 31 b from below into positioning holes 23 a and 23 a formed in the bearing holder 23 of the main body portion 10. Screwed by screws 34 and 34. Therefore, the suspension leg 30 can be connected to the main body 10 with high positional accuracy. As shown in FIG. 2, the base part side connecting parts 32, 32 of the suspension leg 30 are screwed by inserting boss parts 32 b, 32 b from above into positioning holes 51 a, 51 a formed in the pad base 51. , 35. Therefore, the suspension leg 30 can be coupled to the base portion 50 with high positional accuracy. The screws 35 are also part of a plurality of screws for fixing the pad 52 to the pad base 51.

  In the above-described configuration, when the base unit 50 swings with respect to the main body unit 10, the support column 33 repeatedly undergoes elastic deformation. Therefore, a material that has flexibility and excellent durability is selected for the suspension foot 30. In the present embodiment, polypropylene is selected as the material for the suspension leg 30.

  Next, the arrangement of the columns 33 in a state where the main body 10 and the base 50 are connected by the suspension leg 30 will be described.

  As shown in FIG. 3 and FIG. 4, a total of sixteen struts 33 included in the two front and rear suspension legs 30 are disposed around the motor shaft 12 and the eccentric shaft portion 42. The support column 33 having an axis in the vertical direction in the state of the suspension leg 30 alone has an upper end 33a corresponding to the eccentric amount e of the eccentric shaft part 42 in a state where the main body 10 and the base part 50 are connected by the suspension leg 30. In contrast, the position of the lower end 33b is shifted. That is, the suspension leg 30 is installed in a state in which the column 33 is bent. When the base portion 50 swings with respect to the main body portion 10 by the rotation of the motor shaft 12, the center of the lower end 33b of the column 33 is the same as the eccentricity e with respect to the perpendicular from the center of the upper end 33a. Move along a circular path of radius.

  As shown in FIG. 3, the upper ends 33 a of the total 16 columns 33 are arranged on the circumference of the diameter D with the motor shaft 12 as the center. Further, as shown in FIG. 4, the lower ends 33 b of the total 16 columns 33 are arranged on the circumference of the diameter d with the eccentric shaft portion 42 as the center. The diameter D and the diameter d are set equal. By arranging the support columns 33 in this way, it is possible to reduce the variation in the load on all the support columns 33, so that it is possible to prevent the support columns from being broken at an early stage, resulting in the durability of the suspension foot 30. Can be improved.

  Moreover, in the suspension leg 30 of the sander 1 according to the present embodiment, as shown in FIG. 4, the diameter d is set larger than the short side dimension L of the pad base 51 formed as a rectangular shape. With this configuration, the support column 33 can be arranged at a position further away from the center of the pad base 51. Therefore, since the load applied to the support column 33 during the polishing operation can be further reduced, the durability of the suspension leg 30 can be further enhanced.

  Moreover, in the suspension leg 30 of the sander 1 according to the present embodiment, as shown in FIGS. 3 and 4, the upper end 33 a of the support column 33 extends in the front-rear direction and the left-right direction passing through the center of the motor shaft 12 that is the rotation shaft. The lower end 33b of the column 33 is arranged symmetrically with respect to the straight line in the front-rear direction and the left-right direction passing through the center of the eccentric shaft part 42. Therefore, the load on each column 33 can be more equalized, and the durability of the suspension leg 30 can be further improved.

  In particular, in a sander in which the gripping portion 22 is extended in the front-rear direction as in the sander 1 according to the present embodiment, the load imbalance on each column 33 tends to increase. Therefore, by adopting the above-described configuration, a remarkable effect can be expected in improving the durability of the suspension leg 30.

  In the present embodiment, four struts 33 are arranged in four regions divided by straight lines in the front-rear direction and the left-right direction passing through the center of the motor shaft 12 or the eccentric shaft portion 42. It is also possible to adopt a configuration in which two support columns 33 are arranged in each of the four regions. In this case, the total number of support columns 33 is eight. It is also possible to adopt a configuration in which three support columns 33 are arranged in each of the four regions. In this case, the total number of columns 33 is 12. As described above, in the present invention, the total number of the columns 33 can be set to the most suitable number among multiples of four of eight or more, depending on the shape of the columns 33, the magnitude of the load on the columns 33, and the like. Is possible.

  As mentioned above, although preferred embodiment of this invention was described, the technical scope of this invention is not limited to the range as described in the said embodiment. Various modifications or improvements can be added to the embodiment.

  For example, in the sander 1 according to the above embodiment, the eccentric sleeve 41 is attached to the motor shaft 12 having the vertical axis, but the invention is not limited to this configuration. For example, the motor is placed horizontally so that the axis of the motor shaft is in the front-rear direction, and an eccentric sleeve (eccentric shaft) is attached to the rotary shaft having the vertical axis connected to the motor shaft via a bevel gear. A configuration is also possible.

  In addition, for example, in the sander 1 according to the above-described embodiment, the two suspension legs 30 are divided and arranged in two front and rear positions, but the present invention is not limited to this. For example, it is also possible to adopt a configuration in which two suspension legs are arranged separately in two places on the left and right. Further, for example, it is possible to integrally form two suspension legs. Furthermore, for example, it is also possible to adopt a configuration in which four suspension legs are arranged separately in four places, front, rear, left and right.

1 Sander, 10 Body part, 11 Motor, 12 Motor shaft, 13 Bearing, 14 Fan, 15 Screw, 21 Housing, 22 Gripping part, 23 Bearing holder, 23a Positioning hole, 30 Suspension foot, 31 Body part side connection part, 31a Plate-shaped part, 31b Boss part, 31c hole, 32 Base part side connection part, 32a Plate-shaped part, 32b Boss part, 32c Screw hole, 33 Post, 33a Upper end, 33b Lower end, 34 Screw, 35 Screw, 41 Eccentric sleeve , 42 Eccentric shaft part, 43 collar part, 50 base part, 51 pad base, 51a positioning hole, 51b bearing storage hole, 52 pad, 53 bearing, 54 holding screw, 55 clamping device

Claims (2)

A main body comprising a motor as a drive source, a rotating shaft driven by the motor, and a housing for housing the motor;
A base portion disposed below the main body portion and performing a swinging motion by rotation of an eccentric shaft coupled to the rotation shaft;
In a sander comprising a suspension leg that connects the base part to the main body part so as to be able to swing,
The suspension foot connects the main body part side connecting part connected to the main body part, the base part side connecting part connected to the base part, and connects the main body part side connecting part and the base part side connecting part. A plurality of struts that are elastically deformed by the swinging motion of the base portion are integrally formed,
The plurality of support columns are formed in a cylindrical shape,
The upper ends of the plurality of struts are arranged on a circumference around the rotation axis,
The lower ends of the plurality of support columns are disposed on a circumference centered on the eccentric shaft, and
Ri same diameter der the circumference around the circumference and the eccentricity shaft around said rotating shaft,
The upper ends of the plurality of support columns are disposed symmetrically with respect to a straight line in the front-rear direction and the left-right direction passing through the center of the rotation axis,
The lower ends of the plurality of support columns are disposed symmetrically with respect to a straight line in the front-rear direction and the left-right direction passing through the center of the eccentric shaft,
The total number of the struts is 8 or more, and is a multiple of four . The base portion includes a rectangular pad base,
The base part side connecting part is connected to the pad base,
The sander according to claim 1, wherein the diameter is larger than a short side length of the pad base.

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