JP3884021B2 - Waterproof caster - Google Patents

Description

  The present invention relates to a waterproof caster that is mounted and used on a transport cart, a stretcher, and other various traveling devices.

  Rain, dust, water, mud, chemicals, etc. splashed from the ground contact surface from the outside into the rotary bearing part of the wheel or the slewing bearing part of the yoke, and these bearing parts are corroded early or conversely. As for casters for preventing grease, iron powder, etc. from leaking out from the bearing portion, for example, Japanese Utility Model Laid-Open Nos. 54-15876, 56-20242, and Japanese Patent Laid-Open Nos. 6-143907 and 6-143907 are disclosed. No. 2000-85308 and Japanese Patent No. 3159668 have been proposed.

Of these, particularly in the case of the invention of Japanese Patent No. 3159668, a seal material (75) capable of covering the rotation bearing (42) of the wheel (40) as shown in FIG. 12, and a turning bearing (32) of the yoke (30). 3 and a sealing material (70) capable of closing the mutual gap between the yoke (30) and the base (20) as shown in FIG. 11 is described. Therefore, it is considered to be a known technique that is most approximate to the present invention.
Japanese Utility Model Publication No. 54-15876 Japanese Utility Model Publication No. 56-20242 JP-A-6-143907 JP 2000-85308 A Japanese Patent No. 3159668

  However, as for the sealing material (75) of the known invention, first, it is made of a plastic material such as synthetic rubber, and is attached so as to rotate integrally with the boss (step) (45) of the wheel (40). However, the boss portion (45) and the outer ring (42b) in which the bearing (42) rotates and the wheel support plate (33) in the yoke (30) are sandwiched between each other. In order to reduce the frictional resistance with the inner ring (42a) in the fixed state of (42), even if the projecting ridge (76) is engraved on the sealing material (75), the sealing material (75) becomes the yoke (30). When the wheel (40) is strongly contacted with the wheel support plate (33), the wheel (40) does not rotate lightly and smoothly due to a large frictional resistance. Mutual with plate (33) Water, mud, chemicals, or the like enter the bearing (42) from the outside through the gap or the mutual gap between the protrusion (76) with the reduced frictional resistance and the inner ring (42a). ) Is likely to leak grease, iron powder, etc. As a result, high accuracy is required to the extent that the sealing material (75) is sandwiched, and it is difficult to always ensure a stable assembly state.

  Further, since the seal member (75) is interposed between the bearing (42) of the wheel (40) and the wheel support plate (33) of the yoke (30), the wheel support plate (33). 2), the rim diameter of the wheel (40) as shown in FIGS. 2, 3, and 7 is greatly extended so as to participate in the complete covering action of the sealing material (75). 40) Spokes and other shaped patterns are concealed, resulting in a decrease in makeup effect.

  Next, regarding the cap (60) covering the turning bearing (32) of the yoke (30), it is fitted and bonded from below to the opening surface of the bearing support (31) in the yoke (30). Therefore, it is necessary to form the cap (60) from a synthetic resin material such as nylon into a tapered shape as shown in FIGS. 5 (A) and 5 (B). Special adhesives must also be used to fit and integrate to 31).

  Even if the cap (60) is fitted and bonded to the opening surface of the bearing support (31) from below, the cap (60) does not have the overall elasticity, and thus repeatedly receives vibrations and shocks during use. In this case, this cannot be absorbed, there is a risk of dropping due to the aging of the adhesive, and the durability is also poor.

  Furthermore, as for the sealing material (70) that closes the mutual gap between the bearing support (31) and the base (20), this is also made of a synthetic resin material such as nylon, but has a cross section as shown in FIG. Since it has an inverted L-shape, even if the ridge (71) is engraved on the flat portion (73) of the tent, it absorbs the unbalanced load acting on the turning bearing (32) by itself, It is impossible to ensure a stable sealed state at all times.

  When the parallelism between the bearing support base (31) and the base (20) is lost so that the yoke (30) is inclined by receiving the offset load, the base (20) In order to reduce the frictional resistance, water, mud, chemicals, etc. easily enter the bearing (32) from the outside through the ridges (71) formed on the flat portion (73) of the sealing material (70). .

  The present invention aims to improve such various problems, and in order to achieve the object, in claim 1, in claim 1, a mounting base for a transport cart and other various traveling devices,

  A vertical swivel support shaft that is fixedly integrated into the center of the pedestal in a penetrating state;

  An approximately inverted U-shaped yoke pivotably mounted on the pivot shaft via a ball bearing;

  A bottom seal cap that covers the pivot shaft and the yoke pivot ball bearing from below;

  A horizontal axle fixedly mounted horizontally at the lower ends of a pair of left and right sides that form the yoke;

  A traveling wheel pivotally supported freely through a pair of left and right ball bearings on the axle,

  In a waterproof caster comprising a boss of the traveling wheel and a pair of left and right side seal covers covering the wheel bearing for rotating the wheel,

  The bottom seal cap is formed from an elastic material such as rubber or soft synthetic resin into a substantially U-shaped cross section, and only the restoring elastic force accompanying the expansion operation of the bottom seal cap and the ball bearing for turning the yoke While making it tightly integrated into the covering state from below,

  The inner races of the ball bearings for wheel rotation are formed so as to extend outward longer than the outer races, and between the long inner race and the side surface of the yoke, the inner race is almost larger in diameter than the boss of the traveling wheel. While sandwiching and fixing each of the conical saucer type side decorative covers,

  Each piece of the side seal cover is also shaped from an elastic material similar to the bottom seal cap into a substantially bowl shape having an inner race escape center opening with an opening diameter larger than the inner race of the wheel bearing for ball rotation,

  A large inward opening flange having a substantially U-shaped cross section in the side seal cover is tightly integrated with each of the traveling wheel bosses in a state of being covered with each other, and a corresponding inward opening flange of the side decorative cover is used. Siege,

  Similarly, the small outwardly opening leg seat having a generally trumpet cross-section in the side seal cover is elastically lightly supported in the middle part of the side decorative cover.

  A second aspect dependent on the first aspect is characterized in that a ring-shaped reinforcing rib is continuously extended from the vicinity of the upper edge of the opening of the bottom seal cap.

  Further, according to claim 3, which is also dependent on claim 1, the top surface and the pedestal forming the yoke by the substantially conical disc spring type seal washer formed from a hard synthetic resin such as polypropylene and nylon having excellent heat resistance and smoothness. The mutual gap | interval with is sealed in the sealed state.

  Further, in claim 4 subordinate to claim 3, the ring-shaped mounting convex seat having an opening diameter larger than that of the pivot support shaft opening opening the seal washer on the top surface of the yoke, and the diameter continuously projecting from the ring-shaped mounting convex seat. As an overall almost conical disc spring type with a large conical skirt flange,

  While fitting the mounting convex seat into the recessed groove recessed from the bottom surface of the pedestal in the positioning state,

  The skirt flange is brought into close contact with the top surface of the yoke in an elastically biased state.

  In the configuration of the present invention described in claim 1, a bottom seal cap having a substantially U-shaped cross section made of an elastic material such as rubber or soft synthetic resin can be used in an expansion operation without using a special adhesive. Because it is tightly integrated with the pivoting shaft of the yoke and its pivoting ball bearing from the bottom by being surrounded and tightly integrated by only restoring elastic pressure, not only the assembly workability is remarkably improved, but also the vibration during use Even if repeated impacts are received, there is no risk of accidental dropout, and there is an effect that the yoke turning ball bearing can be maintained in a stable and reliable sealed state.

  On the other hand, each of the wheel rotation ball bearings that pivot the traveling wheel to the axle surrounds the large inward opening flange of the side seal cover that is tightly integrated with the traveling wheel boss. The side decorative cover is covered with a corresponding inwardly-opening flange, and the base of the side-sealing cover with the inwardly-opening flange having a large diameter is provided on the side seal cover. The wheel rotation ball bearing can be kept in a stable and reliable sealed state, and the side decorative cover also provides the appearance cosmetic effect of the running wheel. It can be improved.

  In addition, the inner race of the wheel bearing for ball rotation is formed so as to extend longer outward than the outer race, and the side decorative cover is stably sandwiched between the long inner race and the side surface of the yoke. In addition to being attached and fixed, the outer side trumpet-shaped open leg seat with a small diameter of the side seal cover is only slightly elastically supported in the middle part of the side decorative cover. Therefore, anyone can easily and conveniently perform these assembly operations, and a stable assembly state can be ensured at all times.

  Furthermore, the inner race escape center port of the side seal cover literally has an opening diameter larger than the diameter of the inner race in the wheel bearing for wheel rotation so as not to come into contact with the inner race. Even if the inward opening flange of the cover surrounds the corresponding inward opening flange of the side seal cover, there is a certain gap that does not come into contact with each other, so that it does not touch the traveling wheel. A light and smooth rotating action of the traveling wheel can be obtained without giving resistance.

  If the structure of Claim 2 is employ | adopted, the possibility that the said bottom seal cap will expand early from the opening upper edge part, or a crack will be effective by the overhang | projection thickening of a link-shaped reinforcement rib. Can be prevented and help to improve durability.

  In particular, if the configuration of claim 3 is adopted, a seal washer that closes the upper and lower mutual gaps between the pedestal and the yoke is formed from a hard synthetic resin rich in heat resistance and smoothness into a substantially conical disc spring type. Therefore, even if the yoke is swiveled, there is no risk that the yoke will be worn out, and even if the yoke tilts due to a biased load, the biased load can be absorbed by itself, It has the effect of maintaining a stable sealed state at all times.

  In that case, if the configuration is adopted in claim 4, even if the substantially conical disc spring type seal washer is simply sandwiched between the base and the yoke, there is a risk of misalignment of the ring-shaped mounting convex seat with respect to the concave groove of the base. While it can be surely prevented by the fitting lock, the conical skirt flange of the seal washer also meets the inclination of the yoke subjected to the uneven load, but there is no fear of rising from the top surface, Since it exhibits an elastic deformation action that follows this, the sealing effect of the above-mentioned yoke-slewing ball bearing can be further enhanced, and its stability is remarkably excellent.

  Hereinafter, a specific configuration of the present invention will be described in detail with reference to the drawings. In FIGS. 1 to 4 showing the entire waterproof caster according to the present invention, (T) is a transport cart or a stretcher (emergency transport vehicle). It is a mounting base for various other travel devices (not shown), and is made of a substantially square thick stainless steel plate. (1) is a bolt receiving hole for the attachment, and is preferably distributed in the four corners of the pedestal (T) as an ellipse.

  (2) is a vertical swivel support shaft that passes through the center of the circular concave step surface (3) in the pedestal (T), and the large head portion (2a) has a concave step surface ( 3) It is fixed by crimping. (2b) is a bearing receiving step provided at a midway height position of the turning support shaft (2), and receives and regulates a yoke turning ball bearing described later. Similarly, (2c) is a tail end portion of the pivot support shaft (2), which is caulked and integrated with the ball bearing for pivoting the yoke to keep the ball bearing from dropping off.

  (Y) is a yoke of a thick stainless steel plate, which is shaped in an inverted U shape from a horizontal top surface (4) and a pair of side surfaces (5) facing left and right symmetrically. In 4), the turning support shaft outlet (6) is opened in a circular shape. Then, the yoke (Y) is inserted into the turning support shaft (2) from below through the turning support shaft escape opening (6) on the top surface (4) and is fitted.

  (B1) is a steel ball bearing for pivotally mounting such a yoke (Y) to the swivel support shaft (2), which is also inserted into the swivel support shaft (2) from below and is fitted. The outer race (8) and the surrounding cover (9) are connected to the yoke (Y) with respect to the inner race (7) fixed by caulking the tail end (2c) of the pivot support shaft (2). Rotating action integrally.

  Reference numeral (10) denotes a bottom seal cap that entirely surrounds the tail end (2c) of the pivot support shaft (2) and the ball bearing (B1) for pivoting the yoke, such as rubber and soft synthetic resin. The elastic material is formed into a substantially U-shaped cross section, and the tail end portion (2) of the swivel support shaft (2) only by the restoring elastic force accompanying its own expansion operation without using any adhesive. 2c) and the yoke turning ball bearing (B1) are closely integrated with each other in a state of covering from below.

  In this case, since the ring-shaped reinforcing rib (10a) is continuously and integrally extended from the vicinity of the upper edge of the opening of the bottom seal cap (10), the thickness of the ring bearing against the periphery of the ball bearing (B1) for turning the yoke is increased. The biting force can be given up, and the possibility of peeling due to impact or aging during use can be prevented.

  Further, (11) closes a fixed mutual gap (C1) (for example, about 2 mm) facing the circular concave step surface (3) of the pedestal (T) and the corresponding top surface (4) of the yoke (Y). This is a seal washer that is formed from a hard synthetic resin such as polypropylene or nylon having a heat resistance of about 80 ° C. or higher and smoothness into a substantially conical disc spring type as shown in FIG.

  In other words, the seal washer (11) has a ring-shaped mounting convex seat (11a) having an opening diameter (d1) larger than the pivot support shaft escape port (6) of the top surface (4) of the yoke (Y), There is provided a conical skirt flange (11b) having a large diameter that continuously and integrally projects, and the mounting convex seat (11a) is slightly upward from the lower surface of the circular concave step surface (3) of the pedestal (T). In the recessed groove (12) that is depressed, the skirt flange (11b) is protruded and locked to the top surface (4) of the yoke (Y) while being fitted and locked in a stable positioning state. Are closely attached.

  The head (2a) of the swivel support shaft (2) under an urging state in which the seal washer (11) is elastically sandwiched between the base (T) and the yoke (Y). And the tail end portion (2c) are respectively caulked and integrated with the base (T) and the yoke turning ball bearing (B1).

  As a result, the material of the seal washer (11) is excellent in sliding performance, and combined with the fact that the seal washer (11) is shaped into an overall conical disc spring type, it gives a gentle resistance to the turning action of the yoke (Y). If the parallelism between the top surface (4) and the pedestal (T) is lost so that the yoke (Y) is inclined by receiving an eccentric load, the seal washer (11) The skirt flange (11b) is elastically deformed in a follow-up manner and can absorb the above-mentioned unbalanced load by itself, and the mutual gap (C1) between the pedestal (T) and the yoke (Y) facing each other is always reliably sealed. From this point, there is no possibility that water, mud, dust, chemicals, etc. may enter the ball bearing (B1).

  On the other hand, a steel axle (S) is horizontally and horizontally fixed on the lower ends of the left and right side surfaces (5) facing each other in the yoke (Y). This consists of a bolt (13) penetrating the left and right side surfaces (5) of the yoke (Y), and a fixing nut (14) fastened to the tip screw portion (13a), as shown in FIGS. It goes without saying that the position eccentric from the turning support shaft (2) by a certain distance (L) forward or backward extends in a relationship orthogonal to the turning support shaft (2).

  (15) is a steel sleeve inserted and fitted into such an axle (S), and by tightening a fixing nut (14) against the through bolt (13), both side surfaces of the yoke (Y) ( 5) Secure the left and right mutual spacing constant. (B2) is a pair of left and right ball bearings that are further inserted into the sleeve (15) through the steel distance collar (16) and rotate the traveling wheel (W) to the axle (S). It is pivoted freely. (17), (18) and (19) respectively show the boss, rim and tire of the traveling wheel (W), compared to the boss (17) and rim (18) made of steel or hard synthetic resin. The tire (19) is made of rubber, nylon, urethane, elastomer or the like.

  Needless to say, each of the ball bearings for rotating the wheel (B2) is made of steel and has a pair of left and right symmetrical forms. In particular, the wheel bearing ball bearing (B2) is restrained by being fixed to the axle (S) and the sleeve (15). The inner race (20) is formed so as to extend longer outward than the outer race (21) that can rotate integrally with the traveling wheel (W) and the surrounding cover (22).

  (23) is a pair of left and right symmetrical sides sandwiched and fixed between the inner race (20) of the ball bearing (B2) for rotating the wheel and the side surface (5) of the yoke (Y). A decorative cover, which is plastically processed into a conical saucer type facing a thin stainless steel plate, and has an inward opening flange (23a) that is larger in diameter than the boss (17) of the traveling wheel (W). The boss (17) faces the periphery. Although not shown on the surface of such a side decorative cover (23), various uneven patterns also serving as reinforcing ribs are plastic processed.

  Further, (24) is a pair of left and right symmetrical side seal covers for covering the wheel rotation ball bearing (B2), which is the same rubber as the bottom seal cap (10) of the yoke turning ball bearing (B1). It is formed from a soft synthetic resin into a substantially bowl shape as shown in FIG.

  That is, each of the side seal covers (24) includes a large inward opening flange (24a) having a substantially U-shaped cross section that fits the boss (17) of the traveling wheel (W), and the side decorative cover (23). ), And the outwardly open leg seat (24b) having a concentric circular shape. And the inwardly opening flange (24a) are slightly larger than the diameter (D) of the inner race (20) as the inner race escape center port (24c) of the wheel bearing for ball rotation (B2). It is dimensioned to the opening diameter (d2).

  Each of the side seal covers (24) is inserted into the inner race (20) of the wheel bearing (B2) for rotating the wheel through the inner race escape center opening (24c). The large inward opening flange (24a) is attached to the boss (17) of the traveling wheel (W) and bonded and integrated, while the remaining small outward opening leg seat (24b) It is elastically supported by the flat middle part of the decorative cover (23).

  In that case, the large-diameter inward opening flange (24a) of the side seal cover (24) is not in contact with the corresponding inward opening flange (24a) of the side decorative cover (23) surrounding it. Rather, a certain gap (C2) (for example, about 3 mm) is secured between them. As long as this is done, the inwardly facing opening flange (24a) of the side seal cover (24) is not bonded and integrated with the boss (17) of the traveling wheel (W), but is applied as a concavo-convex fitting state between them. You can just keep it in close contact.

  As a result, the outwardly open leg seat (24b) of the side seal cover (24) is only elastically lightly supported on the side decorative cover (23) of the traveling wheel (W). Thus, the traveling wheel (W) rotates smoothly without receiving a large resistance, and there is no possibility that the outwardly opening leg seat (24b) will be worn out.

  Moreover, due to the double structure of the side seal cover (24) and the side decorative cover (23) surrounding the side seal cover (24), it is continuous from the base of the inward opening flange (24a) having a large diameter of the side seal cover (24). Then, the outwardly opening leg seat (24b) having a small diameter is bent back and bent into a trumpet shape, so that the wheel rotating ball bearing (B2) can be always kept in a reliable sealed state. There is no possibility that water, mud, dust, chemicals, or the like may enter the bearing (B2) from the outside, or grease or iron powder or the like may leak from the inside of the ball bearing (B2).

  In the embodiment shown in FIGS. 1 to 4, the steel sleeve (15) is inserted between the ball bearing for wheel rotation (B2) and the axle (S). By omitting the installation of (15) and using a thick axle (S) as shown in the modified embodiment of FIG. 7 and a wheel rotation ball bearing (B2) of the same size, a relatively large traveling wheel (W) may be pivotally supported.

  Even if the insertion of the sleeve (15) is omitted, since the wheel bearing ball bearing (B2) has a long inner race (20), the left and right pair in parallel and the distance collar (16) This is because the space between the left and right sides (5) of the yoke (Y) can be ensured correctly. In addition, since the other structure in such a modified embodiment is substantially the same as the said embodiment of FIGS. 1-4, it only fills the corresponding code | symbol with FIGS. 1-4 in the FIG. Detailed description thereof is omitted.

It is a side view of the waterproof caster concerning the present invention. It is an expanded sectional view which follows the 2-2 line of FIG. It is sectional drawing which follows the 3-3 line of FIG. FIG. 4 is a cross-sectional view taken along line 4-4 of FIG. It is a slope view which extracts and shows a seal washer. It is a slope view which extracts and shows a side seal cover. It is sectional drawing which shows the deformation | transformation embodiment of this invention corresponding to FIG.

Explanation of symbols

(1) ・ Bolt receiving hole (2) ・ Swivel support shaft (2a) ・ Head (2b) ・ Bearing receiving step (2c) ・ Tail end (3) ・ Circular concave step (4) ・ Top ( 5) ・ Side (6) ・ Revolving support shaft (7) ・ Inner race (8) ・ Outer race (9) ・ Enclosure cover (10) ・ Bottom seal cap (10a) ・ Reinforcement rib (11) ・ Seal Washer (11a), mounting convex seat (11b), skirt flange (11), groove (13), through bolt (13a), tip screw (14), fixing nut (15), sleeve (16), distance collar (17) · Boss (18) · Rim (19) · Tire (20) · Inner race (21) · Outer race (22) · Enclosure cover (23) · Side decorative cover (23a) · Inward opening flange ( 24) ・ Side seal cover (24a) ・ Inward opening flange (24b) ・ Outward opening leg seat (24c) Inner race escape center port (B1) ・ Ball bearing for turning the yoke (B2) ・ Ball bearing for wheel rotation (C1), vertical clearance (C2), air gap (S), axle (T), pedestal (Y), yoke (W), running wheel (D), diameter (d1) (d2), opening diameter

Claims (4)

A mounting base (T) for a transport cart and other various traveling devices;
A vertical swivel support shaft (2) fixed and integrated in a penetrating state to the center of the pedestal (T);
A substantially inverted U-shaped yoke (Y) pivotably mounted on the pivot shaft (2) via a ball bearing (B1);
A bottom seal cap (10) for covering the swivel support shaft (2) and the yoke swivel ball bearing (B1) from below;
A horizontal axle (S) fixedly mounted horizontally on the lower ends of a pair of left and right sides (5) facing the yoke (Y);
A traveling wheel (W) rotatably supported by a pair of right and left ball bearings (B2) on the axle (S),
In a waterproof caster comprising a boss (17) of the traveling wheel (W) and a pair of left and right side seal covers (24) covering the wheel rotation ball bearing (B2),
The bottom seal cap (10) is formed from an elastic material such as rubber or soft synthetic resin into a substantially U-shaped cross section, and the swivel support shaft (2) is formed only by a restoring elastic force accompanying its own expansion operation. And the ball bearing (B1) for pivoting the yoke from the lower side in close contact with each other,
Inner races (20) of the wheel bearing for ball rotation (B2) are formed so as to extend longer outward than the outer race (21), and the inner race (20) and the side surface (5) of the yoke (Y) are formed. ) And sandwiching and fixing a substantially conical saucer-type side decorative cover (23) having a diameter larger than that of the boss (17) of the traveling wheel (W).
Each of the side seal covers (24) is also made of the same elastic material as the bottom seal cap (10), so that the inner race escapes with an opening diameter (d2) larger than the inner race (20) of the wheel bearing for ball rotation (B2). Shaped in a nearly bowl shape with a center opening (24c),
A large inward opening flange (24a) having a substantially U-shaped cross section in the side seal cover (24) is tightly integrated with the boss (17) of the traveling wheel (W) so as to cover each other. Surrounded by a corresponding inwardly opening flange (23a) of the side decorative cover (23),
Similarly, the small outwardly opening leg seat (24b) having a generally trumpet cross-section in the side seal cover (24) is only elastically supported in the middle of the side decorative cover (23). Waterproof caster.   The waterproof caster according to claim 1, wherein a ring-shaped reinforcing rib (10a) is continuously extended integrally from the vicinity of the upper edge of the opening of the bottom seal cap (10).   The top face (4) and the pedestal (T) that form the yoke (Y) by a substantially conical disc spring type seal washer (11) molded from a hard synthetic resin such as polypropylene or nylon, which has excellent heat resistance and smoothness. The waterproof caster according to claim 1, wherein the mutual gap (C1) is closed in a sealed state. The seal washer (11) is connected to a ring-shaped mounting convex seat (11a) having a larger opening diameter (d1) than the pivot support shaft escape opening (6) opening on the top surface (4) of the yoke (Y). As an overall substantially conical disc spring type with a large conical skirt flange (11b) projecting integrally,
While the mounting convex seat (11a) is fitted and locked in the positioning state into the concave groove (12) recessed from the lower surface of the pedestal (T),
The waterproof caster according to claim 3, characterized in that the skirt flange (11b) is brought into close contact with the top surface (4) of the yoke (Y) in an elastically biased state.

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