JP2010156559A - Tape measure case braking structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a closed tape measure braking structure which obtains proper braking force even in the case of a small tape measure, and in which deviation in braking force is small among products and a tape is easily pulled out. <P>SOLUTION: The tape measure case braking structure is provided with: a tape measure case housing a wound tape measure tape; and a drum which is rotatably mounted on a shaft part protruded along a thickness direction in the tape measure case and around which the tape measure tape is wound, wherein braking force is obtained by bringing the drum into press contact with an inner surface part of the tape measure case when the tape is pulled out from the tape measure case. A circumferential edge part of the drum is partially brought into press contact with the inner surface part the tape measure case. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an improvement in a braking structure for a tape measure case.

In general, a so-called “sealed” tape measure is widely used in which a metal tape measure tape has a circular shape on the side and can be stored in a case made of synthetic resin or the like.
In such a sealed tape measure, when a metal tape is pulled out, the drawn tape has a predetermined weight, so that the drum on which the tape measure tape is wound by the inertia force of the tape itself. If a tape measure tape comes out of the case in large quantities, or the tape measure spreads in the case and the tape measure tape sticks to the inner peripheral surface of the case, causing the drum to idle, making it easy to pull out the tape. There may not be.

  An example of such a sealed tape measure is as shown in FIG. 8 (1). A tape measure 80a is made of synthetic resin and has a case 81 formed in a disk shape having a predetermined thickness. A synthetic resin drum 84 that is rotatably mounted on a shaft portion 82 formed in the center portion of the case 81 and is disposed in an opening 83 formed in one side surface portion, and on which a tape is wound. ing.

  Then, a leaf spring 85 is built in the base end portion of the shaft portion 82, and the drum 84 is pressed against the case inner peripheral surface portion 86 on the opposite base end side of the shaft portion 82 by the urging force of the leaf spring 85, or Alternatively, as shown in FIG. 8 (2), a tape measure 80 b that obtains a braking force against the rotation of the drum 84 by disposing a metal ring member 87 between the drum 84 and the case inner peripheral surface portion 86. was there.

  However, in the tape measure 80a, 80b configured as described above, since a braking force against the rotation of the drum 84 is always applied, a predetermined force is required to pull out the tape when the tape is pulled out. Since the tape is difficult to pull out and the leaf spring 85 and the ring member 87 are required, the number of parts increases and the manufacturing cost increases.

In order to solve such a problem, as shown in FIGS. 9 (1) and 9 (2), the applicant of the present patent application has conventionally used a drum 84 facing the inner surface of the case where the drum 84 is in sliding contact. A swash plate cam follower 89 is provided at the base end portion 88, and a swash plate cam portion 90 is provided around the shaft portion 82 so as to face the swash plate cam follower 89. When rotating in the opening direction, as shown in FIG. 9 (2), the swash plate cam follower 89 rotates in the ascending direction of the swash plate cam portion 90, and the opening side peripheral portion 91 of the drum 84 is moved. When the drum 84 is pressed against the inner peripheral surface 86 of the case to generate a braking force and the drum 84 rotates in the direction of winding the tape, as shown in FIG. The drum 84 is opened by rotating in the descending direction. A tape measure braking structure has been proposed in which the side peripheral edge portion 91 is separated from the inner peripheral surface portion 86 of the case so as to eliminate the braking force (Patent Document 1).

However, in such a conventional tape measure braking structure, the rotation of the drum 84 causes the swash plate cam follower 89 to rotate in the ascending direction of the swash plate cam portion 90, thereby opening the peripheral edge portion of the drum 84. When 91 is in pressure contact with the inner peripheral surface portion 86 of the case, the entire peripheral edge portion of the opening side peripheral edge portion 91 of the drum 84 is in pressure contact with the case inner peripheral surface portion 86.
As a result, as shown in FIG. 10, when the operator pulls out the tape, the entire peripheral edge of the drum 84 is pressed against the inner peripheral edge 86 of the case 81, and as a result, a large braking force is suddenly generated. There was a problem that it was not easy to use because a big shock was transmitted to the hand pulling out the tape.

  Such a situation is particularly noticeable in the case of a small tape measure. In the case of a small tape measure, the tape length is short (20 m to 30 m), so a very large braking force is instantaneously generated and braking is not performed. There was a problem that it was too effective and it was difficult to pull out the tape.

Further, when the opening side peripheral edge portion 89 of the drum 84 and the case inner peripheral surface portion 86 do not contact the entire surface portion uniformly due to a design error or an attachment error, even a slight error may occur. If the two surface portions do not contact uniformly, as a result, a too large braking force cannot be exhibited.
Therefore, there are cases where a large braking force is produced depending on individual products due to manufacturing errors or attachment errors, and cases where such a case is not the case, and variations among products may occur.

Japanese Patent Laid-Open No. 9-287901

  Accordingly, the present invention is to provide a braking structure having a tape measure in which a moderate braking force can be obtained even with a small tape measure, and there is no variation in the braking force between products, and the tape can be easily pulled out.

In order to solve the above-mentioned problem, in the invention according to claim 1, the tape can be rotated by a tape measure case for storing the wound tape measure tape, and a shaft portion protruding in the thickness direction in the tape measure case. And a drum around which the tape measure tape is wound, and when the tape is pulled out of the tape measure case, the drum is pressed against the inner side surface of the tape measure case to obtain a braking force. In the braking structure of the tape measure case, the peripheral portion of the drum is partially brought into pressure contact with the inner side surface portion of the tape measure case.
Therefore, even when the drum is brought into pressure contact with the inner side surface of the tape measure case to obtain a braking force, there is no situation in which the entire peripheral edge portion of the drum is in pressure contact with the inner side surface portion of the tape measure case.

  According to a second aspect of the present invention, the tape measure case is formed in an overall disk shape having a thickness dimension capable of accommodating a tape measure tape, and an inner side surface portion of the tape measure case is provided at a peripheral portion of the drum. Brake parts that can be pressed against each other are provided at intervals.

The invention according to claim 3 is characterized in that the braking portion is configured to be elastically pressed against the inner side surface portion of the tape measure case.
According to a fourth aspect of the present invention, the tape measure case has a circular opening on one side surface in the thickness direction, and the drum has a main body disposed in the circular opening and the main body. And a winding portion around which the tape is wound, and a brake portion capable of being in pressure contact with an inner peripheral edge portion of the opening portion is provided on a peripheral edge of the main body portion. And

In the invention according to claim 5, the braking portion has a base portion formed in plural at a predetermined interval around the periphery of the main body portion, and a protrusion portion that protrudes in the axial direction from the base portion. It is characterized by.
According to a sixth aspect of the present invention, the base portion includes a leg portion fixed to the outer peripheral surface portion of the drum, and a support in which the protruding portion is formed by being spaced apart from the outer peripheral surface portion from the leg portion. And a portion.

  In the invention according to claim 7, the base portion is formed in a plane U shape, and has a pair of legs provided at both ends of the support portion, and the protrusion is the center in the length direction of the support portion. It is formed in a part, and it is comprised so that it may be flexible by the elastic deformation of the said support part along the axial direction of a drum.

  In the first and second aspects of the invention, even when the drum is pressed against the inner side surface of the tape measure case to obtain a braking force as in the prior art, the entire peripheral edge of the drum is the tape measure case. Since it is not pressed against the inner side surface portion, it is possible to prevent a situation in which a large braking force acts instantaneously, places a burden on the user's hand, and is difficult to handle.

  As a result, even if it is a small tape measure and the length of the tape is short, a very large braking force is generated instantaneously, the braking is too effective, and it is difficult to pull out the tape on the contrary. be able to.

  In the inventions according to claims 3 to 7, since the braking part is configured to be able to elastically press against the inner side surface part of the tape measure case, the inventions according to claims 1 and 2 are provided. In addition to the above effect, the braking portion can more smoothly abut against the inner side surface portion of the tape measure case, and a frictional force can be gradually generated. Moreover, even if there is a manufacturing error or mounting error on the tape measure case side or the drum side and there is a situation contrary to the originally assumed contact state, the above error can be easily absorbed, It is possible to effectively avoid a situation in which there is a difference in the generated braking force due to various manufacturing errors or mounting errors.

A brake structure for a tape measure case according to the present invention will be described in detail with reference to the drawings.
As shown in FIGS. 1 and 2, the tape measure 10 to which the braking structure of the tape measure case according to the present embodiment is applied has a predetermined thickness dimension for accommodating the metal tape measure tape 11 wound inside. And a tape measure case 12 made of a synthetic resin formed in a substantially disk shape.

As shown in FIG. 2, the tape measure case 12 is rotatably mounted on a shaft portion 13 projecting in the thickness direction in the tape measure case 12 and the synthetic tape on which the tape measure tape 11 is wound. A drum 14 made of steel is provided.
The tape measure case 12 has a circular opening 15 on one side surface in the thickness direction, and the drum 14 is integrally formed of synthetic resin, and the circular opening 15
A main body portion 16 disposed on the main body portion 16 and a winding portion 17 connected to the main body portion 16 and around which the tape 11 is wound.

A swash plate cam follower 24 is provided at the base end portion 23 of the drum 14, and on the tape measure case 12 side, around the shaft portion 13, facing the swash plate cam follower 24. A swash plate cam portion 25 is provided.
Therefore, when the drum 14 rotates in the direction to open the tape measure 11, the swash plate cam follower 24 rotates in the ascending direction of the swash plate cam 25, and the opening side peripheral portion 26 of the drum 14 is moved. When the drum 14 rotates in the direction in which the tape tape 11 is taken up, the drum 14 is rotated in the descending direction of the swash plate cam portion 25 when the drum 14 rotates in the direction of winding the tape tape 11. 14 opening side peripheral edge portions 26 are separated from the case inner side surface portion 27 so that the braking force is eliminated.

As shown in FIGS. 2 to 5, a brake portion 18 that can be pressed against the inner peripheral edge portion 19 of the circular opening 15 is provided on the peripheral edge of the main body portion 16.
In the present embodiment, the circular opening 15 is formed over substantially the entire area of one side surface portion 17 in the thickness direction of the measuring tape case 12, An inner peripheral edge portion 19 with which the brake portion 18 of the main body portion 16 of the drum 14 abuts is formed, and is a plane that is provided at a substantially right angle from the inner peripheral edge portion 19 and in which the side surface portion 20 of the brake portion 18 is in sliding contact. A circular protrusion 28 is formed over the entire circumference.

  As shown in FIG. 3, in the present embodiment, eight braking portions 18 are formed on the peripheral portion of the main body portion 16 at a predetermined interval. As shown in FIGS. 2 to 4, the braking portion 18 is formed in a substantially U shape on the entire side surface, and a plurality of base portions 21 formed at predetermined intervals around the periphery of the main body portion 16, and the base portion 21. And a protrusion 22 formed to protrude in the axial direction (thickness direction of the main body 16).

The base portion 21 is formed between a pair of leg portions 29, 29 fixed to the outer peripheral surface portion 31 of the drum, and the pair of leg portions 29, 29, and is disposed apart from the outer peripheral surface portion 31. And a support portion 30 on which a protrusion 22 is formed.
The pair of leg portions 29 and 29 are each formed in a substantially rectangular parallelepiped shape, and the support portion 30 is provided so as to be spanned at the upper end portions of the leg portions 29 and 29. The base 21 is formed with the same curvature as that of the main body 16.

  The protrusion 22 is formed in a substantially rectangular parallelepiped shape having a width dimension equal to the width dimension of the support section 30 and a length dimension of 1/3 of the support section 30 at the center in the length direction of the support section 30. The upper surface portion is formed as the contact surface portion 32.

Below, the effect | action of the braking structure of the tape measure case which concerns on this Embodiment is demonstrated.
As shown in FIG. 1, when the metal tape measure tape 11 is pulled out from the tape measure case 10 according to the present embodiment through the ring member 31 at the tip, the swash plate cam follower fixed to the drum 14. As the portion 24 rotates in the ascending direction of the swash plate cam portion 25 provided on the tape measure case 12 side, the swash plate cam driven portion 24 pushes the drum 14 toward the circular opening portion 15 along the axial direction. As a result, the braking portion 18 is pressed against the inner peripheral edge portion 19 of the tape measure case 12.

  In this case, as shown in FIGS. 6 (1) and 6 (2), the abutment surface portion 32 of the protrusion 22 constituting the braking portion 18 starts to slidably contact the inner peripheral edge portion 19, and then further the swash plate. When the cam follower 24 is pressed toward the inner peripheral edge 19, the protrusion 22 is pressed along the thickness direction of the support 30. In this case, as shown in FIG. 6 (3), since the support portion 30 is integrally formed so as to be spanned between the pair of leg portions 29, 29, the support portion 30 is in the axial direction of the drum 14. It is elastically deformed and bent.

  As a result, the elastic deformation of the support portion 30 absorbs the pressure contact force applied to the inner peripheral edge portion 19 by the swash plate cam driven portion 24, so that the entire peripheral edge portion of the drum 14 is inward as in the prior art. Unlike the case where the entire periphery is pressed firmly, the generated frictional force can be flexibly reduced.

As a result, as shown in FIGS. 6 (1) to (3) and FIG. 7, the protrusion 22 starts to come into pressure contact with the inner peripheral edge 19 from a non-contact state and is further pressed completely. Since the pressure contact force is absorbed by the elastic deformation of the support portion 30 as described above, the frictional force can be gradually generated.
As a result, in the braking structure for the tape measure case according to the present embodiment, unlike the conventional case where the entire peripheral edge of the drum 14 is configured to press-contact the entire inner peripheral edge of the case, the braking is performed. Since only the protrusion 22 constituting the portion 18 is configured to be in pressure contact with the inner peripheral edge 19 of the case, the contact area of the drum 14 with the inner peripheral edge 19 of the case is reduced, so that the generated friction The force can be reduced as compared with the conventional case.

  Further, when the support portion 30 on which the protrusion 22 constituting the braking portion 18 is formed is formed between the pair of leg portions 29 and 29 as described above, when the protrusion 22 presses against the inner peripheral edge portion 19. Since it is configured to be elastically deformed and bent along the axial direction of the shaft portion 13, it is possible to generate a braking force while appropriately absorbing excessive frictional force, and a conventional tape measure tape. When 11 is pulled out, a situation in which a large braking force is suddenly generated can be prevented.

As a result, it is possible to provide an easy-to-use tape measure that does not suddenly give an impact to the hand when the user pulls out the tape measure tape 11.
Further, in the braking structure for the tape measure case according to the present embodiment, eight braking portions 18 are formed at a predetermined interval on the peripheral portion of the main body portion 16, and the braking portions 18 are As shown in FIGS. 2 to 5, the base 21 is formed in a substantially U-shape as a whole and is formed at a predetermined interval around the periphery of the main body 16, and the base 21 has an axial direction (the thickness of the main body 16. Since the weight of the tape measure tape 11 varies depending on the length of the tape measure tape 11 and the inertial force acting on the tape measure tape 11 when it is pulled out is also configured. Although different, depending on the length of the tape measure 11, for example, the size of the protrusion 22, the surface area of the contact surface 32 of the protrusion 22, and the width dimension of the support 30 on which the protrusion 22 is formed, and Protrusion by changing the material as appropriate 2 it is possible to adjust the elastic force when pressed against the inner peripheral surface 19 of the tape measure case 12, it can be manufactured tape measure with the most appropriate braking force. As a result, it is possible to provide various types of tape measure having appropriate braking force according to the type of product.

  In the above embodiment, the case where eight braking portions 18 are provided as a whole has been described as an example, but the number of braking portions 18 is not limited to the above embodiment. Further, the specific structure of the braking portion 18 is not limited to the above embodiment.

  Moreover, in this Embodiment, although the case where the tape measure tape 11 was metal was demonstrated to the example, it is not limited to the said embodiment, It can apply also regarding the tape measure which consists of a synthetic resin tape measure tape. it can.

  The present invention is widely applicable to a case of a sealed tape measure.

It is a perspective view which shows one Embodiment of the braking structure of the tape measure case which concerns on this invention. 1 shows an embodiment of a tape measure case braking structure according to the present invention, and is a cross-sectional view taken along line 2-2 of FIG. 1 is a plan view showing a main body portion constituting a drum on which a tape measure tape is wound, showing an embodiment of a tape measure case braking structure according to the present invention. It is a perspective view which shows one Embodiment of the braking structure of the tape measure case which concerns on this invention, and shows the main-body part which comprises the drum by which a tape measure tape is wound. 1 is a perspective view showing an embodiment of a braking structure for a tape measure case according to the present invention and independently showing a braking portion provided in a main body portion constituting a drum on which a tape measure tape is wound. 1 shows an embodiment of a braking structure for a tape measure case according to the present invention, in which a protrusion of a braking portion provided on a main body constituting a drum around which a tape measure tape is wound, and an inner side of the tape measure case of the protrusion It is explanatory sectional drawing which expands and shows the state of press contact to a peripheral surface part partially. 1 shows one embodiment of a braking structure for a tape measure case according to the present invention, wherein a protrusion of a braking portion provided on a main body portion constituting a drum around which a tape measure tape is wound, and an inner peripheral surface portion of the tape measure case Cross-sectional view showing a partially enlarged state of the pressure contact, and the relationship between the braking portion and the inner peripheral edge of the case between the non-contact state and the state after the contact, and the magnitude of the friction force Is a graph with the ordinate as the vertical axis. It is sectional drawing which shows generally the braking structure of the conventional tape measure case. It is sectional drawing which shows the example of improvement of the braking structure of the conventional tape measure case, and shows the case where the swash plate cam part and the swash plate cam follower part are provided. FIG. 2 is a partially enlarged cross-sectional view showing a state of pressure contact between the peripheral edge of the drum and the inner peripheral surface of the case in a conventional tape measure case braking structure, and a drum between the non-contact state and the state after contact. It is the graph which expressed the relationship between a peripheral part and the inner peripheral part of a case as a horizontal axis, and the magnitude | size of the frictional force as the vertical axis | shaft.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Tape measure 11 Tape measure tape 12 Tape measure case 13 Shaft part 14 Drum 15 Circular opening part 16 Main-body part 17 Winding part 18 Braking part 19 Inner peripheral edge part 20 Side part 21 Base part 22 Projection part 23 Base end part 24 Swash plate cam follower part 25 Swash plate cam portion 26 Opening side peripheral portion 27 Case inner side surface portion 28 Projection portion 29 Leg portion 30 Support portion 31 Outer peripheral surface portion 80 Tape measure 81 Case 82 Shaft portion 83 Opening portion 84 Drum 85 Plate spring 86 Inner peripheral surface portion 87 Ring member 88 Base end portion 89 Swash plate cam driven portion 90 Swash plate cam portion 91 Opening peripheral edge portion

Claims (7)

A tape measure case that houses the wound tape measure tape, and a drum that is rotatably mounted on a shaft projecting along the thickness direction in the tape measure case, and on which the tape measure tape is wound, In the braking structure of the tape measure case configured to obtain a braking force by pressing the drum against the inner side surface of the tape measure case when the tape is pulled out from the tape measure case,
A braking structure for a tape measure case, wherein the peripheral portion of the drum is partially brought into pressure contact with an inner side surface portion of the tape measure case.   The tape measure case is formed in an overall disk shape having a thickness dimension capable of accommodating a tape measure tape inside, and a braking portion capable of being in pressure contact with the inner side surface portion of the tape measure case is spaced apart from the peripheral portion of the drum. 2. The tape measure case braking structure according to claim 1, wherein the structure is provided.   The brake structure for a tape measure case according to claim 2, wherein the brake portion is configured to be able to elastically press against the inner side surface portion of the tape measure case.   The tape measure case has a circular opening on one side surface in the thickness direction, the drum is connected to the main body disposed in the circular opening, the main body, and the tape is wound thereon. The tape measure case according to claim 1, wherein a brake portion is provided on the periphery of the main body portion, the brake portion being capable of being pressed against the inner periphery of the opening. Braking structure. The braking portion includes a plurality of base portions formed at predetermined intervals on the periphery of the main body portion;
5. A braking structure for a tape measure case according to claim 4, further comprising: a protrusion that protrudes in the axial direction from the base.   The base portion includes a leg portion fixed to the outer peripheral surface portion of the drum, and a support portion that is connected to the leg portion and spaced from the outer peripheral surface portion, and is formed with the protrusion. The braking structure for a tape measure case according to claim 5. The base is formed in a substantially U-shaped plane, the legs are provided in a pair, and the support is provided between the pair of legs,
The said protrusion is formed in the center part of the length direction of the said support part, and it is comprised so that it may be flexible by the elastic deformation of the said support part along the axial direction of a drum. Braking structure for the tape measure case.