JPH0232392Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention provides at least three or more parallel sockets for fitting and supporting bolt heads, such as in a multi-axis nut runner, and each of these sockets This invention relates to a bolt tightening device that tightens a plurality of bolts at the same time.

(Prior Art) In a conventional multi-axis nut runner, the axial mounting positions (projection heights) of a plurality of sockets arranged in parallel are set to be the same (in other words,
The mounting positions in the axial direction were set so that the front end surfaces of each socket were located on the same plane in the axial direction. For example, see Utility Model Application Publication No. 58-150435).

However, in this case, when tightening the bolts, the front end surface of each socket is pressed against the head of the corresponding bolt, and the bolt head is inserted into the circular hole formed in the front end surface of the socket. If the front end surface of each socket contacts the head of each bolt at the same time, each socket must be aligned with its corresponding bolt at the same time. The problem was that the bolt head could not be fitted into the circular hole of the bolt, making it difficult to align the axes of the socket and bolt, resulting in poor workability.

(Purpose of the invention) The present invention is an attempt to solve the problems pointed out in the above-mentioned section of the prior art.
The purpose of this invention is to facilitate the alignment of each socket and each corresponding bolt, thereby improving workability in bolt tightening work.

(Means for Achieving the Object) As a means for achieving the above object, the present invention provides a method for connecting a predetermined pair of sockets out of at least three or more sockets arranged in parallel directions to the other sockets. It protrudes further forward than the socket in the axial direction and is larger than the depth corresponding to the depth of the circular hole formed in the front end surface of the socket.

(Function) In the present invention, by the above-mentioned means, only by aligning the axes of a predetermined pair of sockets and their corresponding bolts among a plurality of sockets, the axes of other sockets and their corresponding bolts can be aligned. This provides the effect that alignment is performed automatically.

(Embodiment) Hereinafter, a preferred embodiment of the present invention will be described with reference to FIGS. 1 and 2.

FIG. 1 shows a multi-axis (six-axis) nut runner 1 used for tightening hub bolts for fastening and fixing a tire wheel 11 to a tire hub in an automobile production line as an example of a bolt tightening device. There is.

This nut runner 1 has a built-in motor and is mounted on a front end surface 2a of a nut runner main body 2 which is suspended and supported by a balancer rope 12 so as to be movable up and down.
It is constructed by arranging six sockets 3A, 3B, etc., which will be described later, on the same circumference and at equal pitches in the circumferential direction. These six sockets 3A, 3B...
As will be described later, they all have the same basic configuration, but only the six sockets 3A, 3B...
Of these, a pair of sockets, such as the first socket 3A and the fourth socket 3D, which face each other across the axis of the nut runner body 2 in the radial direction, and the other four sockets, namely, the second socket 3B and the third socket. 3C, the fifth socket 3E, and the sixth socket 3F are different in their axial mounting positions (projection heights). Hereinafter, the structures of these two types of sockets having different axial mounting positions will be described in detail with reference to FIG. 2, respectively, for the first socket 3A and the sixth socket 3F.

The first socket 3A is open at its axial center on its front end surface 3Aa, and has hub bolts 10A and 10B.
A circular hole 8 with a depth S ₀ and an inner diameter that allows rotation of the hexagonal head of...
continuous to the bottom of the hub bolt 10A, 10
A fitting hole 9 having a hexagonal cross section and an appropriate depth is formed so that the head of B... can be fitted and supported in a non-relative rotation state. Of the circular hole portion 8 and the fitting hole portion 9, the circular hole portion 8 is for aligning the axis of the first socket 3A and the first hub bolt 10A corresponding to the first socket 3A. On the other hand, the fitting hole portion 9 is connected to the head 10 of the first hub bolt 10A.
The first hub bolt 10A is engaged with Aa in the rotational direction to rotationally drive the first hub bolt 10A in the tightening direction.

Further, on the rear end surface 3Ab of the first socket 3A, a guide hole 13A having a rectangular cross section is formed toward the axial direction of the first socket 3A. In this guide hole 13A, a socket drive shaft having a rectangular cross section is disposed protruding from the front end surface 2a of the nut runner body 2 and is rotationally driven by a motor (not shown) built in the nut runner body 2. 5A is slidably inserted into the first
The socket 3A is rotated integrally with the socket drive shaft 5A by engagement between the inner surface of the guide hole 13A of the first socket 3A and the outer surface of the socket drive shaft 5A in the direction of rotation of the socket drive shaft 5A. . Furthermore, a pin 6 is inserted into the elongated hole 7A formed in the socket drive shaft 5A, passing through the guide hole 13A in the radial direction and attached to the first socket 3A side. Further, a spring 4 is provided between the first socket 3A and the front end surface 2a of the nut runner main body 2, which acts to cause the first socket 3A to always protrude outward. Therefore, this first socket 3A has the spring force of the spring 4 and a pressing force that acts in a direction to press the first socket 3A against the spring force of the spring 4 toward the nut runner main body 2 (i.e., the first hub bolt). 10A), and its most protruding position (the position shown by the solid line in FIG. 2) is between the pin 6 and the front end surface 7 of the elongated hole 7A.
The maximum retracted position (FIG. 2, chain line indicated position, reference numeral 3A') is regulated by the contact between the pin 6 and the rear end surface 7Ab of the elongated hole 7A (stroke S ₁ ). When tightening the first hub bolt 10A using the first socket 3A configured in this way, first place the front end surface 3Aa of the first socket 3A against the head 10Aa of the first hub bolt 10A. Head 10
Aa is inserted into the circular hole 8 of the first socket 3A. This completes the alignment (alignment) between the first socket 3A and the first hub bolt 10A. At this time, the side wall direction of the circular hole portion 8 and the first hub bolt 1
If the side wall direction of the head 10Aa of 0A completely matches, the head 10Aa of the first hub bolt 10A
is inserted into the fitting hole 9 as it is, and the fitting hole 9
Since the first hub bolt 10A is fitted and supported in a non-relative rotation state, tightening of the first hub bolt 10A is immediately started by rotating the first socket 3A.
If it is longer than that, the head 10Aa of the first hub bolt 10A comes into contact with the shoulder 8a formed at the bottom of the circular hole 8 and is prevented from fitting into the fitting hole 9 side. Therefore, in this case, the first socket 3A is rotated while the pressing force is applied between the first socket 3A and the first hub bolt 10A, and the shoulder 8a of the circular hole 8 and the first hub bolt 10A are rotated. head 10
The head 10Aa of the first hub bolt 10A is inserted into the fitting hole 9 by releasing the engagement with the first hub bolt 10A in the axial direction. That is, according to the first socket 3A, the first hub bolt 10A is once inserted into the circular hole 8.
After fitting the head 10Aa and aligning the axes between the two, rotate the first socket 3A and press it against the first hub bolt 10A to prevent the rotation of the first socket 3A and the first hub bolt 10A. The head 10Aa of the first hub bolt 10A is smoothly attached regardless of the relative position in the direction.
is inserted into the fitting hole 9 and the first hub bolt 10A
Tightening is started.

The sixth socket 3F has the same structure as the first socket 3A as shown in FIG. 2, and here, each member of the first socket 3A is attached to each member of the sixth socket 3F shown in FIG. By assigning the reference numerals corresponding to the reference numerals , to avoid redundant explanation, two points of difference from the first socket 3A, that is, the axial stroke and the axial mounting position, will be described in detail.

The stroke and axial mounting position of the sixth socket 3F are set as follows in relation to the first socket 3A. That is, the front end surface 3Fa of the sixth socket 3F at its most protruding position (FIG. 2, the position shown by the solid line) is larger than the front end surface 3Aa of the first socket 3A at its most protruding position.
The first socket _3A is moved back by a distance S3 (in other words, the first socket 3A is projected forward by a distance _S3 from the sixth socket 3F). still,
This retreat dimension S ₃ is equal to the depth dimension S ₀ of the circular hole 8.
(dimension S ₃ > S ₀ ).

Also, the sixth socket 3F is at the most retracted position (second
3F'), the front end surface 3Fa' is located at the same axial position as the front end surface 3Aa' of the first socket 3A' which is positioned at the most retracted position. It is set. Therefore, the stroke _S2 of the sixth socket 3F is equal to the stroke _S1 of the first socket 3A and the first socket 3.
Projection dimension of A (retraction dimension of 6th socket 3F) S ₃
The difference is (S ₁ − S ₃ ).

As mentioned above, the first socket 3A and the sixth socket 3F have a dimension S ₃ in front of the sixth socket 3F when the bolt is not tightened.
When the bolt is tightened (when the socket is pressed against the hub bolt side), the front end surface 3Aa of the first socket 3A and the front end surface 3Fa of the sixth socket 3F are located at the same position in the axial direction. The relative positions in the axial direction are set as follows.

Therefore, as mentioned above, there are two types with different axial mounting positions.
When simultaneously tightening hub bolts 10A, 10B, etc. using a 6-axis nut runner 1 equipped with different types of sockets, the nut runner 1 is attached to each hub bolt 10.
A, 10B... side, first socket 3A
The head 1 of the first hub bolt 10A corresponds to the circular hole 8 of the fourth socket 3D and the circular hole 8 of the fourth socket 3D.
0Aa and the head 10Da of the fourth hub bolt 10D are fitted, all other sockets are not engaged with their corresponding hub bolts, so the shafts of the first socket 3A and the first hub bolt 10A are The alignment and the axis alignment of the fourth socket 3D and the fourth hub bolt 10D are performed smoothly without being influenced by other sockets. When the first socket 3A and the first hub bolt 10A and the fourth socket 3D and the fourth hub bolt 10D are aligned, each socket 3A, 3B...
... arrangement pitch and each hub bolt 10A, 10B...
Since the arrangement pitches of ... are set to be the same in advance, the second socket 3B and the second hub bolt 10B, the third socket 3C and the third hub bolt 10
C, 5th socket 3E and 5th hub bolt 10E
The axis alignment of the remaining four sets of the sixth socket 3F and the sixth hub bolt 10F is also performed automatically at the same time even though each socket and each corresponding hub bolt are in a mutually disengaged state. simplification). Therefore, when the alignment of the two sockets, the first socket 3A and the fourth socket 3D, is completed, the operator presses the nut runner 1 toward the hub bolts 10A, 10B, . Each hub bolt 10A, 10B, etc. can be tightened simultaneously by the simple operation of rotating them simultaneously (simplification of work).

(Effect of the invention) As is clear from the above explanation, the bolt tightening device of the invention has at least three bolts in the parallel direction.
A predetermined pair of sockets among the plurality of sockets arranged is made to protrude beyond the depth dimension of the circular hole for axis alignment formed in the front end surface of the other sockets, so that the pair of sockets and this By aligning the sockets with the corresponding bolts, the other sockets and their corresponding bolts can be aligned at the same time.
Compared to conventional bolt tightening devices where all sockets and their corresponding bolts must be aligned at the same time, it is easier to align the sockets and bolts, and the bolts can be aligned easily. This has the practical effect of improving workability during tightening work.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of essential parts of a multi-shaft nut runner according to an embodiment of the present invention, and FIG. 2 is an enlarged vertical sectional view of a first socket and a fifth socket of the nut runner shown in FIG. 1...Multi-axis nut runner, 3A-3F...Socket, 4...Spring, 5A-5F...Socket drive shaft, 6...Pin, 7A-7F...Elongated hole, 8
...Circular hole, 9...Fitting hole, 10A to 10F
...Hub bolt, 11...Tire wheel.

Claims (1)

[Scope of utility model registration request] At least three or more socket drive shafts that are rotationally driven by a motor are arranged parallel to each other, and the front end of each socket drive shaft has an inner diameter that allows rotation of the bolt head. A circular hole portion of a predetermined depth having a dimension and a fitting hole portion of a predetermined depth having a cross-sectional shape that can fit and support the bolt head in a non-relative rotation state are sequentially coaxially formed from the front end side. The sockets formed continuously in the sockets are mounted with the circular holes facing forward, movable in the axial direction, and capable of transmitting torque, and each socket is always held forward by a spring. This is a tightening device for bolts which is biased so as to protrude, when each of the sockets is positioned at its maximum protrusion position by the spring force of a spring. A method for tightening bolts, characterized in that the front end surface of the socket is configured to protrude further in the axial direction than the front end surfaces of other sockets by a dimension corresponding to the depth of the circular hole. Device.